--- /dev/null
+(**************************************************************************)
+(* ___ *)
+(* ||M|| *)
+(* ||A|| A project by Andrea Asperti *)
+(* ||T|| *)
+(* ||I|| Developers: *)
+(* ||T|| The HELM team. *)
+(* ||A|| http://helm.cs.unibo.it *)
+(* \ / *)
+(* \ / This file is distributed under the terms of the *)
+(* v GNU General Public License Version 2 *)
+(* *)
+(**************************************************************************)
+
+(* This file was automatically generated: do not edit *********************)
+
+include "basic_1A/csubst0/props.ma".
+
+include "basic_1A/csubst0/fwd.ma".
+
+include "basic_1A/clear/fwd.ma".
+
+lemma csubst0_clear_O:
+ \forall (c1: C).(\forall (c2: C).(\forall (v: T).((csubst0 O v c1 c2) \to
+(\forall (c: C).((clear c1 c) \to (clear c2 c))))))
+\def
+ \lambda (c1: C).(C_ind (\lambda (c: C).(\forall (c2: C).(\forall (v:
+T).((csubst0 O v c c2) \to (\forall (c0: C).((clear c c0) \to (clear c2
+c0))))))) (\lambda (n: nat).(\lambda (c2: C).(\lambda (v: T).(\lambda (H:
+(csubst0 O v (CSort n) c2)).(\lambda (c: C).(\lambda (_: (clear (CSort n)
+c)).(csubst0_gen_sort c2 v O n H (clear c2 c)))))))) (\lambda (c: C).(\lambda
+(H: ((\forall (c2: C).(\forall (v: T).((csubst0 O v c c2) \to (\forall (c0:
+C).((clear c c0) \to (clear c2 c0)))))))).(\lambda (k: K).(\lambda (t:
+T).(\lambda (c2: C).(\lambda (v: T).(\lambda (H0: (csubst0 O v (CHead c k t)
+c2)).(\lambda (c0: C).(\lambda (H1: (clear (CHead c k t) c0)).(let H2 \def
+(csubst0_gen_head k c c2 t v O H0) in (or3_ind (ex3_2 T nat (\lambda (_:
+T).(\lambda (j: nat).(eq nat O (s k j)))) (\lambda (u2: T).(\lambda (_:
+nat).(eq C c2 (CHead c k u2)))) (\lambda (u2: T).(\lambda (j: nat).(subst0 j
+v t u2)))) (ex3_2 C nat (\lambda (_: C).(\lambda (j: nat).(eq nat O (s k
+j)))) (\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead c3 k t)))) (\lambda
+(c3: C).(\lambda (j: nat).(csubst0 j v c c3)))) (ex4_3 T C nat (\lambda (_:
+T).(\lambda (_: C).(\lambda (j: nat).(eq nat O (s k j))))) (\lambda (u2:
+T).(\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead c3 k u2))))) (\lambda
+(u2: T).(\lambda (_: C).(\lambda (j: nat).(subst0 j v t u2)))) (\lambda (_:
+T).(\lambda (c3: C).(\lambda (j: nat).(csubst0 j v c c3))))) (clear c2 c0)
+(\lambda (H3: (ex3_2 T nat (\lambda (_: T).(\lambda (j: nat).(eq nat O (s k
+j)))) (\lambda (u2: T).(\lambda (_: nat).(eq C c2 (CHead c k u2)))) (\lambda
+(u2: T).(\lambda (j: nat).(subst0 j v t u2))))).(ex3_2_ind T nat (\lambda (_:
+T).(\lambda (j: nat).(eq nat O (s k j)))) (\lambda (u2: T).(\lambda (_:
+nat).(eq C c2 (CHead c k u2)))) (\lambda (u2: T).(\lambda (j: nat).(subst0 j
+v t u2))) (clear c2 c0) (\lambda (x0: T).(\lambda (x1: nat).(\lambda (H4: (eq
+nat O (s k x1))).(\lambda (H5: (eq C c2 (CHead c k x0))).(\lambda (H6:
+(subst0 x1 v t x0)).(eq_ind_r C (CHead c k x0) (\lambda (c3: C).(clear c3
+c0)) (K_ind (\lambda (k0: K).((clear (CHead c k0 t) c0) \to ((eq nat O (s k0
+x1)) \to (clear (CHead c k0 x0) c0)))) (\lambda (b: B).(\lambda (_: (clear
+(CHead c (Bind b) t) c0)).(\lambda (H8: (eq nat O (s (Bind b) x1))).(let H9
+\def (eq_ind nat O (\lambda (ee: nat).(match ee with [O \Rightarrow True | (S
+_) \Rightarrow False])) I (S x1) H8) in (False_ind (clear (CHead c (Bind b)
+x0) c0) H9))))) (\lambda (f: F).(\lambda (H7: (clear (CHead c (Flat f) t)
+c0)).(\lambda (H8: (eq nat O (s (Flat f) x1))).(let H9 \def (eq_ind_r nat x1
+(\lambda (n: nat).(subst0 n v t x0)) H6 O H8) in (clear_flat c c0
+(clear_gen_flat f c c0 t H7) f x0))))) k H1 H4) c2 H5)))))) H3)) (\lambda
+(H3: (ex3_2 C nat (\lambda (_: C).(\lambda (j: nat).(eq nat O (s k j))))
+(\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead c3 k t)))) (\lambda (c3:
+C).(\lambda (j: nat).(csubst0 j v c c3))))).(ex3_2_ind C nat (\lambda (_:
+C).(\lambda (j: nat).(eq nat O (s k j)))) (\lambda (c3: C).(\lambda (_:
+nat).(eq C c2 (CHead c3 k t)))) (\lambda (c3: C).(\lambda (j: nat).(csubst0 j
+v c c3))) (clear c2 c0) (\lambda (x0: C).(\lambda (x1: nat).(\lambda (H4: (eq
+nat O (s k x1))).(\lambda (H5: (eq C c2 (CHead x0 k t))).(\lambda (H6:
+(csubst0 x1 v c x0)).(eq_ind_r C (CHead x0 k t) (\lambda (c3: C).(clear c3
+c0)) (K_ind (\lambda (k0: K).((clear (CHead c k0 t) c0) \to ((eq nat O (s k0
+x1)) \to (clear (CHead x0 k0 t) c0)))) (\lambda (b: B).(\lambda (_: (clear
+(CHead c (Bind b) t) c0)).(\lambda (H8: (eq nat O (s (Bind b) x1))).(let H9
+\def (eq_ind nat O (\lambda (ee: nat).(match ee with [O \Rightarrow True | (S
+_) \Rightarrow False])) I (S x1) H8) in (False_ind (clear (CHead x0 (Bind b)
+t) c0) H9))))) (\lambda (f: F).(\lambda (H7: (clear (CHead c (Flat f) t)
+c0)).(\lambda (H8: (eq nat O (s (Flat f) x1))).(let H9 \def (eq_ind_r nat x1
+(\lambda (n: nat).(csubst0 n v c x0)) H6 O H8) in (clear_flat x0 c0 (H x0 v
+H9 c0 (clear_gen_flat f c c0 t H7)) f t))))) k H1 H4) c2 H5)))))) H3))
+(\lambda (H3: (ex4_3 T C nat (\lambda (_: T).(\lambda (_: C).(\lambda (j:
+nat).(eq nat O (s k j))))) (\lambda (u2: T).(\lambda (c3: C).(\lambda (_:
+nat).(eq C c2 (CHead c3 k u2))))) (\lambda (u2: T).(\lambda (_: C).(\lambda
+(j: nat).(subst0 j v t u2)))) (\lambda (_: T).(\lambda (c3: C).(\lambda (j:
+nat).(csubst0 j v c c3)))))).(ex4_3_ind T C nat (\lambda (_: T).(\lambda (_:
+C).(\lambda (j: nat).(eq nat O (s k j))))) (\lambda (u2: T).(\lambda (c3:
+C).(\lambda (_: nat).(eq C c2 (CHead c3 k u2))))) (\lambda (u2: T).(\lambda
+(_: C).(\lambda (j: nat).(subst0 j v t u2)))) (\lambda (_: T).(\lambda (c3:
+C).(\lambda (j: nat).(csubst0 j v c c3)))) (clear c2 c0) (\lambda (x0:
+T).(\lambda (x1: C).(\lambda (x2: nat).(\lambda (H4: (eq nat O (s k
+x2))).(\lambda (H5: (eq C c2 (CHead x1 k x0))).(\lambda (H6: (subst0 x2 v t
+x0)).(\lambda (H7: (csubst0 x2 v c x1)).(eq_ind_r C (CHead x1 k x0) (\lambda
+(c3: C).(clear c3 c0)) (K_ind (\lambda (k0: K).((clear (CHead c k0 t) c0) \to
+((eq nat O (s k0 x2)) \to (clear (CHead x1 k0 x0) c0)))) (\lambda (b:
+B).(\lambda (_: (clear (CHead c (Bind b) t) c0)).(\lambda (H9: (eq nat O (s
+(Bind b) x2))).(let H10 \def (eq_ind nat O (\lambda (ee: nat).(match ee with
+[O \Rightarrow True | (S _) \Rightarrow False])) I (S x2) H9) in (False_ind
+(clear (CHead x1 (Bind b) x0) c0) H10))))) (\lambda (f: F).(\lambda (H8:
+(clear (CHead c (Flat f) t) c0)).(\lambda (H9: (eq nat O (s (Flat f)
+x2))).(let H10 \def (eq_ind_r nat x2 (\lambda (n: nat).(csubst0 n v c x1)) H7
+O H9) in (let H11 \def (eq_ind_r nat x2 (\lambda (n: nat).(subst0 n v t x0))
+H6 O H9) in (clear_flat x1 c0 (H x1 v H10 c0 (clear_gen_flat f c c0 t H8)) f
+x0)))))) k H1 H4) c2 H5)))))))) H3)) H2))))))))))) c1).
+
+lemma csubst0_clear_O_back:
+ \forall (c1: C).(\forall (c2: C).(\forall (v: T).((csubst0 O v c1 c2) \to
+(\forall (c: C).((clear c2 c) \to (clear c1 c))))))
+\def
+ \lambda (c1: C).(C_ind (\lambda (c: C).(\forall (c2: C).(\forall (v:
+T).((csubst0 O v c c2) \to (\forall (c0: C).((clear c2 c0) \to (clear c
+c0))))))) (\lambda (n: nat).(\lambda (c2: C).(\lambda (v: T).(\lambda (H:
+(csubst0 O v (CSort n) c2)).(\lambda (c: C).(\lambda (_: (clear c2
+c)).(csubst0_gen_sort c2 v O n H (clear (CSort n) c)))))))) (\lambda (c:
+C).(\lambda (H: ((\forall (c2: C).(\forall (v: T).((csubst0 O v c c2) \to
+(\forall (c0: C).((clear c2 c0) \to (clear c c0)))))))).(\lambda (k:
+K).(\lambda (t: T).(\lambda (c2: C).(\lambda (v: T).(\lambda (H0: (csubst0 O
+v (CHead c k t) c2)).(\lambda (c0: C).(\lambda (H1: (clear c2 c0)).(let H2
+\def (csubst0_gen_head k c c2 t v O H0) in (or3_ind (ex3_2 T nat (\lambda (_:
+T).(\lambda (j: nat).(eq nat O (s k j)))) (\lambda (u2: T).(\lambda (_:
+nat).(eq C c2 (CHead c k u2)))) (\lambda (u2: T).(\lambda (j: nat).(subst0 j
+v t u2)))) (ex3_2 C nat (\lambda (_: C).(\lambda (j: nat).(eq nat O (s k
+j)))) (\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead c3 k t)))) (\lambda
+(c3: C).(\lambda (j: nat).(csubst0 j v c c3)))) (ex4_3 T C nat (\lambda (_:
+T).(\lambda (_: C).(\lambda (j: nat).(eq nat O (s k j))))) (\lambda (u2:
+T).(\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead c3 k u2))))) (\lambda
+(u2: T).(\lambda (_: C).(\lambda (j: nat).(subst0 j v t u2)))) (\lambda (_:
+T).(\lambda (c3: C).(\lambda (j: nat).(csubst0 j v c c3))))) (clear (CHead c
+k t) c0) (\lambda (H3: (ex3_2 T nat (\lambda (_: T).(\lambda (j: nat).(eq nat
+O (s k j)))) (\lambda (u2: T).(\lambda (_: nat).(eq C c2 (CHead c k u2))))
+(\lambda (u2: T).(\lambda (j: nat).(subst0 j v t u2))))).(ex3_2_ind T nat
+(\lambda (_: T).(\lambda (j: nat).(eq nat O (s k j)))) (\lambda (u2:
+T).(\lambda (_: nat).(eq C c2 (CHead c k u2)))) (\lambda (u2: T).(\lambda (j:
+nat).(subst0 j v t u2))) (clear (CHead c k t) c0) (\lambda (x0: T).(\lambda
+(x1: nat).(\lambda (H4: (eq nat O (s k x1))).(\lambda (H5: (eq C c2 (CHead c
+k x0))).(\lambda (H6: (subst0 x1 v t x0)).(let H7 \def (eq_ind C c2 (\lambda
+(c3: C).(clear c3 c0)) H1 (CHead c k x0) H5) in (K_ind (\lambda (k0: K).((eq
+nat O (s k0 x1)) \to ((clear (CHead c k0 x0) c0) \to (clear (CHead c k0 t)
+c0)))) (\lambda (b: B).(\lambda (H8: (eq nat O (s (Bind b) x1))).(\lambda (_:
+(clear (CHead c (Bind b) x0) c0)).(let H10 \def (eq_ind nat O (\lambda (ee:
+nat).(match ee with [O \Rightarrow True | (S _) \Rightarrow False])) I (S x1)
+H8) in (False_ind (clear (CHead c (Bind b) t) c0) H10))))) (\lambda (f:
+F).(\lambda (H8: (eq nat O (s (Flat f) x1))).(\lambda (H9: (clear (CHead c
+(Flat f) x0) c0)).(let H10 \def (eq_ind_r nat x1 (\lambda (n: nat).(subst0 n
+v t x0)) H6 O H8) in (clear_flat c c0 (clear_gen_flat f c c0 x0 H9) f t)))))
+k H4 H7))))))) H3)) (\lambda (H3: (ex3_2 C nat (\lambda (_: C).(\lambda (j:
+nat).(eq nat O (s k j)))) (\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead
+c3 k t)))) (\lambda (c3: C).(\lambda (j: nat).(csubst0 j v c
+c3))))).(ex3_2_ind C nat (\lambda (_: C).(\lambda (j: nat).(eq nat O (s k
+j)))) (\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead c3 k t)))) (\lambda
+(c3: C).(\lambda (j: nat).(csubst0 j v c c3))) (clear (CHead c k t) c0)
+(\lambda (x0: C).(\lambda (x1: nat).(\lambda (H4: (eq nat O (s k
+x1))).(\lambda (H5: (eq C c2 (CHead x0 k t))).(\lambda (H6: (csubst0 x1 v c
+x0)).(let H7 \def (eq_ind C c2 (\lambda (c3: C).(clear c3 c0)) H1 (CHead x0 k
+t) H5) in (K_ind (\lambda (k0: K).((eq nat O (s k0 x1)) \to ((clear (CHead x0
+k0 t) c0) \to (clear (CHead c k0 t) c0)))) (\lambda (b: B).(\lambda (H8: (eq
+nat O (s (Bind b) x1))).(\lambda (_: (clear (CHead x0 (Bind b) t) c0)).(let
+H10 \def (eq_ind nat O (\lambda (ee: nat).(match ee with [O \Rightarrow True
+| (S _) \Rightarrow False])) I (S x1) H8) in (False_ind (clear (CHead c (Bind
+b) t) c0) H10))))) (\lambda (f: F).(\lambda (H8: (eq nat O (s (Flat f)
+x1))).(\lambda (H9: (clear (CHead x0 (Flat f) t) c0)).(let H10 \def (eq_ind_r
+nat x1 (\lambda (n: nat).(csubst0 n v c x0)) H6 O H8) in (clear_flat c c0 (H
+x0 v H10 c0 (clear_gen_flat f x0 c0 t H9)) f t))))) k H4 H7))))))) H3))
+(\lambda (H3: (ex4_3 T C nat (\lambda (_: T).(\lambda (_: C).(\lambda (j:
+nat).(eq nat O (s k j))))) (\lambda (u2: T).(\lambda (c3: C).(\lambda (_:
+nat).(eq C c2 (CHead c3 k u2))))) (\lambda (u2: T).(\lambda (_: C).(\lambda
+(j: nat).(subst0 j v t u2)))) (\lambda (_: T).(\lambda (c3: C).(\lambda (j:
+nat).(csubst0 j v c c3)))))).(ex4_3_ind T C nat (\lambda (_: T).(\lambda (_:
+C).(\lambda (j: nat).(eq nat O (s k j))))) (\lambda (u2: T).(\lambda (c3:
+C).(\lambda (_: nat).(eq C c2 (CHead c3 k u2))))) (\lambda (u2: T).(\lambda
+(_: C).(\lambda (j: nat).(subst0 j v t u2)))) (\lambda (_: T).(\lambda (c3:
+C).(\lambda (j: nat).(csubst0 j v c c3)))) (clear (CHead c k t) c0) (\lambda
+(x0: T).(\lambda (x1: C).(\lambda (x2: nat).(\lambda (H4: (eq nat O (s k
+x2))).(\lambda (H5: (eq C c2 (CHead x1 k x0))).(\lambda (H6: (subst0 x2 v t
+x0)).(\lambda (H7: (csubst0 x2 v c x1)).(let H8 \def (eq_ind C c2 (\lambda
+(c3: C).(clear c3 c0)) H1 (CHead x1 k x0) H5) in (K_ind (\lambda (k0: K).((eq
+nat O (s k0 x2)) \to ((clear (CHead x1 k0 x0) c0) \to (clear (CHead c k0 t)
+c0)))) (\lambda (b: B).(\lambda (H9: (eq nat O (s (Bind b) x2))).(\lambda (_:
+(clear (CHead x1 (Bind b) x0) c0)).(let H11 \def (eq_ind nat O (\lambda (ee:
+nat).(match ee with [O \Rightarrow True | (S _) \Rightarrow False])) I (S x2)
+H9) in (False_ind (clear (CHead c (Bind b) t) c0) H11))))) (\lambda (f:
+F).(\lambda (H9: (eq nat O (s (Flat f) x2))).(\lambda (H10: (clear (CHead x1
+(Flat f) x0) c0)).(let H11 \def (eq_ind_r nat x2 (\lambda (n: nat).(csubst0 n
+v c x1)) H7 O H9) in (let H12 \def (eq_ind_r nat x2 (\lambda (n: nat).(subst0
+n v t x0)) H6 O H9) in (clear_flat c c0 (H x1 v H11 c0 (clear_gen_flat f x1
+c0 x0 H10)) f t)))))) k H4 H8))))))))) H3)) H2))))))))))) c1).
+
+lemma csubst0_clear_S:
+ \forall (c1: C).(\forall (c2: C).(\forall (v: T).(\forall (i: nat).((csubst0
+(S i) v c1 c2) \to (\forall (c: C).((clear c1 c) \to (or4 (clear c2 c) (ex3_4
+B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq
+C c (CHead e (Bind b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_:
+T).(\lambda (u2: T).(clear c2 (CHead e (Bind b) u2)))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2))))))
+(ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u:
+T).(eq C c (CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (u: T).(clear c2 (CHead e2 (Bind b) u))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i
+v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c (CHead e1 (Bind b) u1)))))))
+(\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda
+(u2: T).(clear c2 (CHead e2 (Bind b) u2))))))) (\lambda (_: B).(\lambda (_:
+C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda
+(_: T).(csubst0 i v e1 e2))))))))))))))
+\def
+ \lambda (c1: C).(C_ind (\lambda (c: C).(\forall (c2: C).(\forall (v:
+T).(\forall (i: nat).((csubst0 (S i) v c c2) \to (\forall (c0: C).((clear c
+c0) \to (or4 (clear c2 c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1))))))
+(\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear c2
+(CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind
+b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u:
+T).(clear c2 (CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda (e1:
+C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T
+(\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda
+(_: T).(eq C c0 (CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear c2 (CHead e2
+(Bind b) u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda
+(e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2))))))))))))))) (\lambda (n: nat).(\lambda (c2: C).(\lambda (v: T).(\lambda
+(i: nat).(\lambda (H: (csubst0 (S i) v (CSort n) c2)).(\lambda (c:
+C).(\lambda (_: (clear (CSort n) c)).(csubst0_gen_sort c2 v (S i) n H (or4
+(clear c2 c) (ex3_4 B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c (CHead e (Bind b) u1)))))) (\lambda (b:
+B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear c2 (CHead e (Bind
+b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b: B).(\lambda (e1:
+C).(\lambda (_: C).(\lambda (u: T).(eq C c (CHead e1 (Bind b) u))))))
+(\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear c2
+(CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c
+(CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (u2: T).(clear c2 (CHead e2 (Bind b) u2)))))))
+(\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda
+(u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda
+(e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1 e2))))))))))))))))
+(\lambda (c: C).(\lambda (H: ((\forall (c2: C).(\forall (v: T).(\forall (i:
+nat).((csubst0 (S i) v c c2) \to (\forall (c0: C).((clear c c0) \to (or4
+(clear c2 c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1)))))) (\lambda (b:
+B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear c2 (CHead e (Bind
+b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b: B).(\lambda (e1:
+C).(\lambda (_: C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u))))))
+(\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear c2
+(CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (u2: T).(clear c2 (CHead e2 (Bind b) u2)))))))
+(\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda
+(u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda
+(e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2)))))))))))))))).(\lambda (k: K).(\lambda (t: T).(\lambda (c2: C).(\lambda
+(v: T).(\lambda (i: nat).(\lambda (H0: (csubst0 (S i) v (CHead c k t)
+c2)).(\lambda (c0: C).(\lambda (H1: (clear (CHead c k t) c0)).(let H2 \def
+(csubst0_gen_head k c c2 t v (S i) H0) in (or3_ind (ex3_2 T nat (\lambda (_:
+T).(\lambda (j: nat).(eq nat (S i) (s k j)))) (\lambda (u2: T).(\lambda (_:
+nat).(eq C c2 (CHead c k u2)))) (\lambda (u2: T).(\lambda (j: nat).(subst0 j
+v t u2)))) (ex3_2 C nat (\lambda (_: C).(\lambda (j: nat).(eq nat (S i) (s k
+j)))) (\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead c3 k t)))) (\lambda
+(c3: C).(\lambda (j: nat).(csubst0 j v c c3)))) (ex4_3 T C nat (\lambda (_:
+T).(\lambda (_: C).(\lambda (j: nat).(eq nat (S i) (s k j))))) (\lambda (u2:
+T).(\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead c3 k u2))))) (\lambda
+(u2: T).(\lambda (_: C).(\lambda (j: nat).(subst0 j v t u2)))) (\lambda (_:
+T).(\lambda (c3: C).(\lambda (j: nat).(csubst0 j v c c3))))) (or4 (clear c2
+c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda
+(_: T).(eq C c0 (CHead e (Bind b) u1)))))) (\lambda (b: B).(\lambda (e:
+C).(\lambda (_: T).(\lambda (u2: T).(clear c2 (CHead e (Bind b) u2))))))
+(\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v
+u1 u2)))))) (ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear c2 (CHead e2 (Bind
+b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_:
+T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda (e1:
+C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind
+b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_:
+T).(\lambda (u2: T).(clear c2 (CHead e2 (Bind b) u2))))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0
+i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda
+(_: T).(\lambda (_: T).(csubst0 i v e1 e2)))))))) (\lambda (H3: (ex3_2 T nat
+(\lambda (_: T).(\lambda (j: nat).(eq nat (S i) (s k j)))) (\lambda (u2:
+T).(\lambda (_: nat).(eq C c2 (CHead c k u2)))) (\lambda (u2: T).(\lambda (j:
+nat).(subst0 j v t u2))))).(ex3_2_ind T nat (\lambda (_: T).(\lambda (j:
+nat).(eq nat (S i) (s k j)))) (\lambda (u2: T).(\lambda (_: nat).(eq C c2
+(CHead c k u2)))) (\lambda (u2: T).(\lambda (j: nat).(subst0 j v t u2))) (or4
+(clear c2 c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1)))))) (\lambda (b:
+B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear c2 (CHead e (Bind
+b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b: B).(\lambda (e1:
+C).(\lambda (_: C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u))))))
+(\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear c2
+(CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (u2: T).(clear c2 (CHead e2 (Bind b) u2)))))))
+(\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda
+(u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda
+(e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1 e2)))))))) (\lambda
+(x0: T).(\lambda (x1: nat).(\lambda (H4: (eq nat (S i) (s k x1))).(\lambda
+(H5: (eq C c2 (CHead c k x0))).(\lambda (H6: (subst0 x1 v t x0)).(eq_ind_r C
+(CHead c k x0) (\lambda (c3: C).(or4 (clear c3 c0) (ex3_4 B C T T (\lambda
+(b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e
+(Bind b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda
+(u2: T).(clear c3 (CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_:
+C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T
+(\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0
+(CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (u: T).(clear c3 (CHead e2 (Bind b) u)))))) (\lambda (_:
+B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1 e2))))))
+(ex4_5 B C C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind b) u1))))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear
+c3 (CHead e2 (Bind b) u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_:
+C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_:
+B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0
+i v e1 e2))))))))) (K_ind (\lambda (k0: K).((clear (CHead c k0 t) c0) \to
+((eq nat (S i) (s k0 x1)) \to (or4 (clear (CHead c k0 x0) c0) (ex3_4 B C T T
+(\lambda (b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e (Bind b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_:
+T).(\lambda (u2: T).(clear (CHead c k0 x0) (CHead e (Bind b) u2))))))
+(\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v
+u1 u2)))))) (ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear (CHead c k0 x0)
+(CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead c k0 x0) (CHead e2 (Bind b)
+u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1:
+C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2))))))))))) (\lambda (b: B).(\lambda (H7: (clear (CHead c (Bind b) t)
+c0)).(\lambda (H8: (eq nat (S i) (s (Bind b) x1))).(let H9 \def (f_equal nat
+nat (\lambda (e: nat).(match e with [O \Rightarrow i | (S n) \Rightarrow n]))
+(S i) (S x1) H8) in (let H10 \def (eq_ind_r nat x1 (\lambda (n: nat).(subst0
+n v t x0)) H6 i H9) in (eq_ind_r C (CHead c (Bind b) t) (\lambda (c3: C).(or4
+(clear (CHead c (Bind b) x0) c3) (ex3_4 B C T T (\lambda (b0: B).(\lambda (e:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c3 (CHead e (Bind b0) u1))))))
+(\lambda (b0: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead c (Bind b) x0) (CHead e (Bind b0) u2)))))) (\lambda (_: B).(\lambda
+(_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C
+T (\lambda (b0: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c3
+(CHead e1 (Bind b0) u)))))) (\lambda (b0: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (u: T).(clear (CHead c (Bind b) x0) (CHead e2 (Bind b0) u))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i
+v e1 e2)))))) (ex4_5 B C C T T (\lambda (b0: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c3 (CHead e1 (Bind b0) u1)))))))
+(\lambda (b0: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda
+(u2: T).(clear (CHead c (Bind b) x0) (CHead e2 (Bind b0) u2))))))) (\lambda
+(_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1 e2))))))))) (or4_intro1
+(clear (CHead c (Bind b) x0) (CHead c (Bind b) t)) (ex3_4 B C T T (\lambda
+(b0: B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C (CHead c (Bind
+b) t) (CHead e (Bind b0) u1)))))) (\lambda (b0: B).(\lambda (e: C).(\lambda
+(_: T).(\lambda (u2: T).(clear (CHead c (Bind b) x0) (CHead e (Bind b0)
+u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b0: B).(\lambda (e1:
+C).(\lambda (_: C).(\lambda (u: T).(eq C (CHead c (Bind b) t) (CHead e1 (Bind
+b0) u)))))) (\lambda (b0: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u:
+T).(clear (CHead c (Bind b) x0) (CHead e2 (Bind b0) u)))))) (\lambda (_:
+B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1 e2))))))
+(ex4_5 B C C T T (\lambda (b0: B).(\lambda (e1: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (_: T).(eq C (CHead c (Bind b) t) (CHead e1 (Bind b0)
+u1))))))) (\lambda (b0: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_:
+T).(\lambda (u2: T).(clear (CHead c (Bind b) x0) (CHead e2 (Bind b0)
+u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1:
+C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1 e2)))))))
+(ex3_4_intro B C T T (\lambda (b0: B).(\lambda (e: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C (CHead c (Bind b) t) (CHead e (Bind b0) u1))))))
+(\lambda (b0: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead c (Bind b) x0) (CHead e (Bind b0) u2)))))) (\lambda (_: B).(\lambda
+(_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2))))) b c t x0
+(refl_equal C (CHead c (Bind b) t)) (clear_bind b c x0) H10)) c0
+(clear_gen_bind b c c0 t H7))))))) (\lambda (f: F).(\lambda (H7: (clear
+(CHead c (Flat f) t) c0)).(\lambda (H8: (eq nat (S i) (s (Flat f) x1))).(let
+H9 \def (f_equal nat nat (\lambda (e: nat).e) (S i) (s (Flat f) x1) H8) in
+(let H10 \def (eq_ind_r nat x1 (\lambda (n: nat).(subst0 n v t x0)) H6 (S i)
+H9) in (or4_intro0 (clear (CHead c (Flat f) x0) c0) (ex3_4 B C T T (\lambda
+(b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e
+(Bind b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda
+(u2: T).(clear (CHead c (Flat f) x0) (CHead e (Bind b) u2)))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2))))))
+(ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u:
+T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (u: T).(clear (CHead c (Flat f) x0) (CHead e2
+(Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda
+(_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda
+(e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1
+(Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda
+(_: T).(\lambda (u2: T).(clear (CHead c (Flat f) x0) (CHead e2 (Bind b)
+u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1:
+C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1 e2)))))))
+(clear_flat c c0 (clear_gen_flat f c c0 t H7) f x0))))))) k H1 H4) c2
+H5)))))) H3)) (\lambda (H3: (ex3_2 C nat (\lambda (_: C).(\lambda (j:
+nat).(eq nat (S i) (s k j)))) (\lambda (c3: C).(\lambda (_: nat).(eq C c2
+(CHead c3 k t)))) (\lambda (c3: C).(\lambda (j: nat).(csubst0 j v c
+c3))))).(ex3_2_ind C nat (\lambda (_: C).(\lambda (j: nat).(eq nat (S i) (s k
+j)))) (\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead c3 k t)))) (\lambda
+(c3: C).(\lambda (j: nat).(csubst0 j v c c3))) (or4 (clear c2 c0) (ex3_4 B C
+T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e (Bind b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_:
+T).(\lambda (u2: T).(clear c2 (CHead e (Bind b) u2)))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2))))))
+(ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u:
+T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (u: T).(clear c2 (CHead e2 (Bind b) u))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i
+v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind b) u1)))))))
+(\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda
+(u2: T).(clear c2 (CHead e2 (Bind b) u2))))))) (\lambda (_: B).(\lambda (_:
+C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda
+(_: T).(csubst0 i v e1 e2)))))))) (\lambda (x0: C).(\lambda (x1:
+nat).(\lambda (H4: (eq nat (S i) (s k x1))).(\lambda (H5: (eq C c2 (CHead x0
+k t))).(\lambda (H6: (csubst0 x1 v c x0)).(eq_ind_r C (CHead x0 k t) (\lambda
+(c3: C).(or4 (clear c3 c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1))))))
+(\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear c3
+(CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind
+b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u:
+T).(clear c3 (CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda (e1:
+C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T
+(\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda
+(_: T).(eq C c0 (CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear c3 (CHead e2
+(Bind b) u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda
+(e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2))))))))) (K_ind (\lambda (k0: K).((clear (CHead c k0 t) c0) \to ((eq nat
+(S i) (s k0 x1)) \to (or4 (clear (CHead x0 k0 t) c0) (ex3_4 B C T T (\lambda
+(b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e
+(Bind b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda
+(u2: T).(clear (CHead x0 k0 t) (CHead e (Bind b) u2)))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2))))))
+(ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u:
+T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (u: T).(clear (CHead x0 k0 t) (CHead e2 (Bind b)
+u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_:
+T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda (e1:
+C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind
+b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_:
+T).(\lambda (u2: T).(clear (CHead x0 k0 t) (CHead e2 (Bind b) u2)))))))
+(\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda
+(u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda
+(e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1 e2)))))))))))
+(\lambda (b: B).(\lambda (H7: (clear (CHead c (Bind b) t) c0)).(\lambda (H8:
+(eq nat (S i) (s (Bind b) x1))).(let H9 \def (f_equal nat nat (\lambda (e:
+nat).(match e with [O \Rightarrow i | (S n) \Rightarrow n])) (S i) (S x1) H8)
+in (let H10 \def (eq_ind_r nat x1 (\lambda (n: nat).(csubst0 n v c x0)) H6 i
+H9) in (eq_ind_r C (CHead c (Bind b) t) (\lambda (c3: C).(or4 (clear (CHead
+x0 (Bind b) t) c3) (ex3_4 B C T T (\lambda (b0: B).(\lambda (e: C).(\lambda
+(u1: T).(\lambda (_: T).(eq C c3 (CHead e (Bind b0) u1)))))) (\lambda (b0:
+B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead x0 (Bind b)
+t) (CHead e (Bind b0) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b0:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c3 (CHead e1 (Bind
+b0) u)))))) (\lambda (b0: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u:
+T).(clear (CHead x0 (Bind b) t) (CHead e2 (Bind b0) u)))))) (\lambda (_:
+B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1 e2))))))
+(ex4_5 B C C T T (\lambda (b0: B).(\lambda (e1: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (_: T).(eq C c3 (CHead e1 (Bind b0) u1))))))) (\lambda (b0:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead x0 (Bind b) t) (CHead e2 (Bind b0) u2))))))) (\lambda (_: B).(\lambda
+(_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1
+u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_:
+T).(\lambda (_: T).(csubst0 i v e1 e2))))))))) (or4_intro2 (clear (CHead x0
+(Bind b) t) (CHead c (Bind b) t)) (ex3_4 B C T T (\lambda (b0: B).(\lambda
+(e: C).(\lambda (u1: T).(\lambda (_: T).(eq C (CHead c (Bind b) t) (CHead e
+(Bind b0) u1)))))) (\lambda (b0: B).(\lambda (e: C).(\lambda (_: T).(\lambda
+(u2: T).(clear (CHead x0 (Bind b) t) (CHead e (Bind b0) u2)))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2))))))
+(ex3_4 B C C T (\lambda (b0: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u:
+T).(eq C (CHead c (Bind b) t) (CHead e1 (Bind b0) u)))))) (\lambda (b0:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear (CHead x0 (Bind b)
+t) (CHead e2 (Bind b0) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b0:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C
+(CHead c (Bind b) t) (CHead e1 (Bind b0) u1))))))) (\lambda (b0: B).(\lambda
+(_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead x0
+(Bind b) t) (CHead e2 (Bind b0) u2))))))) (\lambda (_: B).(\lambda (_:
+C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda
+(_: T).(csubst0 i v e1 e2))))))) (ex3_4_intro B C C T (\lambda (b0:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C (CHead c (Bind b)
+t) (CHead e1 (Bind b0) u)))))) (\lambda (b0: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (u: T).(clear (CHead x0 (Bind b) t) (CHead e2 (Bind b0) u))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i
+v e1 e2))))) b c x0 t (refl_equal C (CHead c (Bind b) t)) (clear_bind b x0 t)
+H10)) c0 (clear_gen_bind b c c0 t H7))))))) (\lambda (f: F).(\lambda (H7:
+(clear (CHead c (Flat f) t) c0)).(\lambda (H8: (eq nat (S i) (s (Flat f)
+x1))).(let H9 \def (f_equal nat nat (\lambda (e: nat).e) (S i) (s (Flat f)
+x1) H8) in (let H10 \def (eq_ind_r nat x1 (\lambda (n: nat).(csubst0 n v c
+x0)) H6 (S i) H9) in (let H11 \def (H x0 v i H10 c0 (clear_gen_flat f c c0 t
+H7)) in (or4_ind (clear x0 c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1))))))
+(\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear x0
+(CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind
+b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u:
+T).(clear x0 (CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda (e1:
+C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T
+(\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda
+(_: T).(eq C c0 (CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear x0 (CHead e2
+(Bind b) u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda
+(e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2))))))) (or4 (clear (CHead x0 (Flat f) t) c0) (ex3_4 B C T T (\lambda (b:
+B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind
+b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2:
+T).(clear (CHead x0 (Flat f) t) (CHead e (Bind b) u2)))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2))))))
+(ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u:
+T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (u: T).(clear (CHead x0 (Flat f) t) (CHead e2
+(Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda
+(_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda
+(e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1
+(Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda
+(_: T).(\lambda (u2: T).(clear (CHead x0 (Flat f) t) (CHead e2 (Bind b)
+u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1:
+C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2)))))))) (\lambda (H12: (clear x0 c0)).(or4_intro0 (clear (CHead x0 (Flat
+f) t) c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1)))))) (\lambda (b:
+B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead x0 (Flat f)
+t) (CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind
+b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u:
+T).(clear (CHead x0 (Flat f) t) (CHead e2 (Bind b) u)))))) (\lambda (_:
+B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1 e2))))))
+(ex4_5 B C C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind b) u1))))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead x0 (Flat f) t) (CHead e2 (Bind b) u2))))))) (\lambda (_: B).(\lambda
+(_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1
+u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_:
+T).(\lambda (_: T).(csubst0 i v e1 e2))))))) (clear_flat x0 c0 H12 f t)))
+(\lambda (H12: (ex3_4 B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1)))))) (\lambda (b:
+B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear x0 (CHead e (Bind
+b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2))))))).(ex3_4_ind B C T T (\lambda (b: B).(\lambda (e:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1))))))
+(\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear x0
+(CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2))))) (or4 (clear (CHead x0 (Flat f) t)
+c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda
+(_: T).(eq C c0 (CHead e (Bind b) u1)))))) (\lambda (b: B).(\lambda (e:
+C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead x0 (Flat f) t) (CHead e
+(Bind b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda
+(u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b: B).(\lambda (e1:
+C).(\lambda (_: C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u))))))
+(\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear
+(CHead x0 (Flat f) t) (CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda
+(e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C
+C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind b) u1))))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead x0 (Flat f) t) (CHead e2 (Bind b) u2))))))) (\lambda (_: B).(\lambda
+(_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1
+u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_:
+T).(\lambda (_: T).(csubst0 i v e1 e2)))))))) (\lambda (x2: B).(\lambda (x3:
+C).(\lambda (x4: T).(\lambda (x5: T).(\lambda (H13: (eq C c0 (CHead x3 (Bind
+x2) x4))).(\lambda (H14: (clear x0 (CHead x3 (Bind x2) x5))).(\lambda (H15:
+(subst0 i v x4 x5)).(or4_intro1 (clear (CHead x0 (Flat f) t) c0) (ex3_4 B C T
+T (\lambda (b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e (Bind b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_:
+T).(\lambda (u2: T).(clear (CHead x0 (Flat f) t) (CHead e (Bind b) u2))))))
+(\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v
+u1 u2)))))) (ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear (CHead x0 (Flat f)
+t) (CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead x0 (Flat f) t) (CHead e2
+(Bind b) u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda
+(e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2))))))) (ex3_4_intro B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1)))))) (\lambda (b:
+B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead x0 (Flat f)
+t) (CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2))))) x2 x3 x4 x5 H13 (clear_flat x0
+(CHead x3 (Bind x2) x5) H14 f t) H15))))))))) H12)) (\lambda (H12: (ex3_4 B C
+C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0
+(CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (u: T).(clear x0 (CHead e2 (Bind b) u)))))) (\lambda (_:
+B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1
+e2))))))).(ex3_4_ind B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear x0 (CHead e2 (Bind
+b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_:
+T).(csubst0 i v e1 e2))))) (or4 (clear (CHead x0 (Flat f) t) c0) (ex3_4 B C T
+T (\lambda (b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e (Bind b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_:
+T).(\lambda (u2: T).(clear (CHead x0 (Flat f) t) (CHead e (Bind b) u2))))))
+(\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v
+u1 u2)))))) (ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear (CHead x0 (Flat f)
+t) (CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead x0 (Flat f) t) (CHead e2
+(Bind b) u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda
+(e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2)))))))) (\lambda (x2: B).(\lambda (x3: C).(\lambda (x4: C).(\lambda (x5:
+T).(\lambda (H13: (eq C c0 (CHead x3 (Bind x2) x5))).(\lambda (H14: (clear x0
+(CHead x4 (Bind x2) x5))).(\lambda (H15: (csubst0 i v x3 x4)).(or4_intro2
+(clear (CHead x0 (Flat f) t) c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1))))))
+(\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead x0 (Flat f) t) (CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_:
+C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T
+(\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0
+(CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (u: T).(clear (CHead x0 (Flat f) t) (CHead e2 (Bind b) u))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i
+v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind b) u1)))))))
+(\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda
+(u2: T).(clear (CHead x0 (Flat f) t) (CHead e2 (Bind b) u2))))))) (\lambda
+(_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1 e2))))))) (ex3_4_intro B C
+C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0
+(CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (u: T).(clear (CHead x0 (Flat f) t) (CHead e2 (Bind b) u))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i
+v e1 e2))))) x2 x3 x4 x5 H13 (clear_flat x0 (CHead x4 (Bind x2) x5) H14 f t)
+H15))))))))) H12)) (\lambda (H12: (ex4_5 B C C T T (\lambda (b: B).(\lambda
+(e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1
+(Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda
+(_: T).(\lambda (u2: T).(clear x0 (CHead e2 (Bind b) u2))))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0
+i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda
+(_: T).(\lambda (_: T).(csubst0 i v e1 e2)))))))).(ex4_5_ind B C C T T
+(\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda
+(_: T).(eq C c0 (CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear x0 (CHead e2
+(Bind b) u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda
+(e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2)))))) (or4 (clear (CHead x0 (Flat f) t) c0) (ex3_4 B C T T (\lambda (b:
+B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind
+b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2:
+T).(clear (CHead x0 (Flat f) t) (CHead e (Bind b) u2)))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2))))))
+(ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u:
+T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (u: T).(clear (CHead x0 (Flat f) t) (CHead e2
+(Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda
+(_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda
+(e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1
+(Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda
+(_: T).(\lambda (u2: T).(clear (CHead x0 (Flat f) t) (CHead e2 (Bind b)
+u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1:
+C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2)))))))) (\lambda (x2: B).(\lambda (x3: C).(\lambda (x4: C).(\lambda (x5:
+T).(\lambda (x6: T).(\lambda (H13: (eq C c0 (CHead x3 (Bind x2)
+x5))).(\lambda (H14: (clear x0 (CHead x4 (Bind x2) x6))).(\lambda (H15:
+(subst0 i v x5 x6)).(\lambda (H16: (csubst0 i v x3 x4)).(or4_intro3 (clear
+(CHead x0 (Flat f) t) c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1))))))
+(\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead x0 (Flat f) t) (CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_:
+C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T
+(\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0
+(CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (u: T).(clear (CHead x0 (Flat f) t) (CHead e2 (Bind b) u))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i
+v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind b) u1)))))))
+(\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda
+(u2: T).(clear (CHead x0 (Flat f) t) (CHead e2 (Bind b) u2))))))) (\lambda
+(_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1 e2))))))) (ex4_5_intro B C
+C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind b) u1))))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead x0 (Flat f) t) (CHead e2 (Bind b) u2))))))) (\lambda (_: B).(\lambda
+(_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1
+u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_:
+T).(\lambda (_: T).(csubst0 i v e1 e2)))))) x2 x3 x4 x5 x6 H13 (clear_flat x0
+(CHead x4 (Bind x2) x6) H14 f t) H15 H16))))))))))) H12)) H11))))))) k H1 H4)
+c2 H5)))))) H3)) (\lambda (H3: (ex4_3 T C nat (\lambda (_: T).(\lambda (_:
+C).(\lambda (j: nat).(eq nat (S i) (s k j))))) (\lambda (u2: T).(\lambda (c3:
+C).(\lambda (_: nat).(eq C c2 (CHead c3 k u2))))) (\lambda (u2: T).(\lambda
+(_: C).(\lambda (j: nat).(subst0 j v t u2)))) (\lambda (_: T).(\lambda (c3:
+C).(\lambda (j: nat).(csubst0 j v c c3)))))).(ex4_3_ind T C nat (\lambda (_:
+T).(\lambda (_: C).(\lambda (j: nat).(eq nat (S i) (s k j))))) (\lambda (u2:
+T).(\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead c3 k u2))))) (\lambda
+(u2: T).(\lambda (_: C).(\lambda (j: nat).(subst0 j v t u2)))) (\lambda (_:
+T).(\lambda (c3: C).(\lambda (j: nat).(csubst0 j v c c3)))) (or4 (clear c2
+c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda
+(_: T).(eq C c0 (CHead e (Bind b) u1)))))) (\lambda (b: B).(\lambda (e:
+C).(\lambda (_: T).(\lambda (u2: T).(clear c2 (CHead e (Bind b) u2))))))
+(\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v
+u1 u2)))))) (ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear c2 (CHead e2 (Bind
+b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_:
+T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda (e1:
+C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind
+b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_:
+T).(\lambda (u2: T).(clear c2 (CHead e2 (Bind b) u2))))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0
+i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda
+(_: T).(\lambda (_: T).(csubst0 i v e1 e2)))))))) (\lambda (x0: T).(\lambda
+(x1: C).(\lambda (x2: nat).(\lambda (H4: (eq nat (S i) (s k x2))).(\lambda
+(H5: (eq C c2 (CHead x1 k x0))).(\lambda (H6: (subst0 x2 v t x0)).(\lambda
+(H7: (csubst0 x2 v c x1)).(eq_ind_r C (CHead x1 k x0) (\lambda (c3: C).(or4
+(clear c3 c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1)))))) (\lambda (b:
+B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear c3 (CHead e (Bind
+b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b: B).(\lambda (e1:
+C).(\lambda (_: C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u))))))
+(\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear c3
+(CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (u2: T).(clear c3 (CHead e2 (Bind b) u2)))))))
+(\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda
+(u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda
+(e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1 e2))))))))) (K_ind
+(\lambda (k0: K).((clear (CHead c k0 t) c0) \to ((eq nat (S i) (s k0 x2)) \to
+(or4 (clear (CHead x1 k0 x0) c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1))))))
+(\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead x1 k0 x0) (CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_:
+C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T
+(\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0
+(CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (u: T).(clear (CHead x1 k0 x0) (CHead e2 (Bind b) u))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i
+v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind b) u1)))))))
+(\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda
+(u2: T).(clear (CHead x1 k0 x0) (CHead e2 (Bind b) u2))))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0
+i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda
+(_: T).(\lambda (_: T).(csubst0 i v e1 e2))))))))))) (\lambda (b: B).(\lambda
+(H8: (clear (CHead c (Bind b) t) c0)).(\lambda (H9: (eq nat (S i) (s (Bind b)
+x2))).(let H10 \def (f_equal nat nat (\lambda (e: nat).(match e with [O
+\Rightarrow i | (S n) \Rightarrow n])) (S i) (S x2) H9) in (let H11 \def
+(eq_ind_r nat x2 (\lambda (n: nat).(csubst0 n v c x1)) H7 i H10) in (let H12
+\def (eq_ind_r nat x2 (\lambda (n: nat).(subst0 n v t x0)) H6 i H10) in
+(eq_ind_r C (CHead c (Bind b) t) (\lambda (c3: C).(or4 (clear (CHead x1 (Bind
+b) x0) c3) (ex3_4 B C T T (\lambda (b0: B).(\lambda (e: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c3 (CHead e (Bind b0) u1)))))) (\lambda (b0:
+B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead x1 (Bind b)
+x0) (CHead e (Bind b0) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b0:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c3 (CHead e1 (Bind
+b0) u)))))) (\lambda (b0: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u:
+T).(clear (CHead x1 (Bind b) x0) (CHead e2 (Bind b0) u)))))) (\lambda (_:
+B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1 e2))))))
+(ex4_5 B C C T T (\lambda (b0: B).(\lambda (e1: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (_: T).(eq C c3 (CHead e1 (Bind b0) u1))))))) (\lambda (b0:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead x1 (Bind b) x0) (CHead e2 (Bind b0) u2))))))) (\lambda (_: B).(\lambda
+(_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1
+u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_:
+T).(\lambda (_: T).(csubst0 i v e1 e2))))))))) (or4_intro3 (clear (CHead x1
+(Bind b) x0) (CHead c (Bind b) t)) (ex3_4 B C T T (\lambda (b0: B).(\lambda
+(e: C).(\lambda (u1: T).(\lambda (_: T).(eq C (CHead c (Bind b) t) (CHead e
+(Bind b0) u1)))))) (\lambda (b0: B).(\lambda (e: C).(\lambda (_: T).(\lambda
+(u2: T).(clear (CHead x1 (Bind b) x0) (CHead e (Bind b0) u2)))))) (\lambda
+(_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1
+u2)))))) (ex3_4 B C C T (\lambda (b0: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u: T).(eq C (CHead c (Bind b) t) (CHead e1 (Bind b0) u))))))
+(\lambda (b0: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear
+(CHead x1 (Bind b) x0) (CHead e2 (Bind b0) u)))))) (\lambda (_: B).(\lambda
+(e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C
+C T T (\lambda (b0: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C (CHead c (Bind b) t) (CHead e1 (Bind b0) u1)))))))
+(\lambda (b0: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda
+(u2: T).(clear (CHead x1 (Bind b) x0) (CHead e2 (Bind b0) u2))))))) (\lambda
+(_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1 e2))))))) (ex4_5_intro B C
+C T T (\lambda (b0: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C (CHead c (Bind b) t) (CHead e1 (Bind b0) u1)))))))
+(\lambda (b0: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda
+(u2: T).(clear (CHead x1 (Bind b) x0) (CHead e2 (Bind b0) u2))))))) (\lambda
+(_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1 e2)))))) b c x1 t x0
+(refl_equal C (CHead c (Bind b) t)) (clear_bind b x1 x0) H12 H11)) c0
+(clear_gen_bind b c c0 t H8)))))))) (\lambda (f: F).(\lambda (H8: (clear
+(CHead c (Flat f) t) c0)).(\lambda (H9: (eq nat (S i) (s (Flat f) x2))).(let
+H10 \def (f_equal nat nat (\lambda (e: nat).e) (S i) (s (Flat f) x2) H9) in
+(let H11 \def (eq_ind_r nat x2 (\lambda (n: nat).(csubst0 n v c x1)) H7 (S i)
+H10) in (let H12 \def (eq_ind_r nat x2 (\lambda (n: nat).(subst0 n v t x0))
+H6 (S i) H10) in (let H13 \def (H x1 v i H11 c0 (clear_gen_flat f c c0 t H8))
+in (or4_ind (clear x1 c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1))))))
+(\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear x1
+(CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind
+b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u:
+T).(clear x1 (CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda (e1:
+C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T
+(\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda
+(_: T).(eq C c0 (CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear x1 (CHead e2
+(Bind b) u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda
+(e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2))))))) (or4 (clear (CHead x1 (Flat f) x0) c0) (ex3_4 B C T T (\lambda (b:
+B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind
+b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2:
+T).(clear (CHead x1 (Flat f) x0) (CHead e (Bind b) u2)))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2))))))
+(ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u:
+T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (u: T).(clear (CHead x1 (Flat f) x0) (CHead e2
+(Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda
+(_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda
+(e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1
+(Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda
+(_: T).(\lambda (u2: T).(clear (CHead x1 (Flat f) x0) (CHead e2 (Bind b)
+u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1:
+C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2)))))))) (\lambda (H14: (clear x1 c0)).(or4_intro0 (clear (CHead x1 (Flat
+f) x0) c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1)))))) (\lambda (b:
+B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead x1 (Flat f)
+x0) (CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind
+b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u:
+T).(clear (CHead x1 (Flat f) x0) (CHead e2 (Bind b) u)))))) (\lambda (_:
+B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1 e2))))))
+(ex4_5 B C C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind b) u1))))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead x1 (Flat f) x0) (CHead e2 (Bind b) u2))))))) (\lambda (_: B).(\lambda
+(_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1
+u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_:
+T).(\lambda (_: T).(csubst0 i v e1 e2))))))) (clear_flat x1 c0 H14 f x0)))
+(\lambda (H14: (ex3_4 B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1)))))) (\lambda (b:
+B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear x1 (CHead e (Bind
+b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2))))))).(ex3_4_ind B C T T (\lambda (b: B).(\lambda (e:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1))))))
+(\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear x1
+(CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2))))) (or4 (clear (CHead x1 (Flat f) x0)
+c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda
+(_: T).(eq C c0 (CHead e (Bind b) u1)))))) (\lambda (b: B).(\lambda (e:
+C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead x1 (Flat f) x0) (CHead e
+(Bind b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda
+(u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C T (\lambda (b: B).(\lambda (e1:
+C).(\lambda (_: C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u))))))
+(\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear
+(CHead x1 (Flat f) x0) (CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda
+(e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C
+C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind b) u1))))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead x1 (Flat f) x0) (CHead e2 (Bind b) u2))))))) (\lambda (_: B).(\lambda
+(_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1
+u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_:
+T).(\lambda (_: T).(csubst0 i v e1 e2)))))))) (\lambda (x3: B).(\lambda (x4:
+C).(\lambda (x5: T).(\lambda (x6: T).(\lambda (H15: (eq C c0 (CHead x4 (Bind
+x3) x5))).(\lambda (H16: (clear x1 (CHead x4 (Bind x3) x6))).(\lambda (H17:
+(subst0 i v x5 x6)).(or4_intro1 (clear (CHead x1 (Flat f) x0) c0) (ex3_4 B C
+T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e (Bind b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_:
+T).(\lambda (u2: T).(clear (CHead x1 (Flat f) x0) (CHead e (Bind b) u2))))))
+(\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v
+u1 u2)))))) (ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear (CHead x1 (Flat f)
+x0) (CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead x1 (Flat f) x0) (CHead e2
+(Bind b) u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda
+(e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2))))))) (ex3_4_intro B C T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1)))))) (\lambda (b:
+B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead x1 (Flat f)
+x0) (CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2))))) x3 x4 x5 x6 H15 (clear_flat x1
+(CHead x4 (Bind x3) x6) H16 f x0) H17))))))))) H14)) (\lambda (H14: (ex3_4 B
+C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C
+c0 (CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (u: T).(clear x1 (CHead e2 (Bind b) u)))))) (\lambda (_:
+B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i v e1
+e2))))))).(ex3_4_ind B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear x1 (CHead e2 (Bind
+b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_:
+T).(csubst0 i v e1 e2))))) (or4 (clear (CHead x1 (Flat f) x0) c0) (ex3_4 B C
+T T (\lambda (b: B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e (Bind b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_:
+T).(\lambda (u2: T).(clear (CHead x1 (Flat f) x0) (CHead e (Bind b) u2))))))
+(\lambda (_: B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v
+u1 u2)))))) (ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u: T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (u: T).(clear (CHead x1 (Flat f)
+x0) (CHead e2 (Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b:
+B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0
+(CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (u2: T).(clear (CHead x1 (Flat f) x0) (CHead e2
+(Bind b) u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda
+(e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2)))))))) (\lambda (x3: B).(\lambda (x4: C).(\lambda (x5: C).(\lambda (x6:
+T).(\lambda (H15: (eq C c0 (CHead x4 (Bind x3) x6))).(\lambda (H16: (clear x1
+(CHead x5 (Bind x3) x6))).(\lambda (H17: (csubst0 i v x4 x5)).(or4_intro2
+(clear (CHead x1 (Flat f) x0) c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1))))))
+(\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead x1 (Flat f) x0) (CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda
+(_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C
+T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0
+(CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (u: T).(clear (CHead x1 (Flat f) x0) (CHead e2 (Bind b) u))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i
+v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind b) u1)))))))
+(\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda
+(u2: T).(clear (CHead x1 (Flat f) x0) (CHead e2 (Bind b) u2))))))) (\lambda
+(_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1 e2))))))) (ex3_4_intro B C
+C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0
+(CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (u: T).(clear (CHead x1 (Flat f) x0) (CHead e2 (Bind b) u))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i
+v e1 e2))))) x3 x4 x5 x6 H15 (clear_flat x1 (CHead x5 (Bind x3) x6) H16 f x0)
+H17))))))))) H14)) (\lambda (H14: (ex4_5 B C C T T (\lambda (b: B).(\lambda
+(e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1
+(Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda
+(_: T).(\lambda (u2: T).(clear x1 (CHead e2 (Bind b) u2))))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0
+i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda
+(_: T).(\lambda (_: T).(csubst0 i v e1 e2)))))))).(ex4_5_ind B C C T T
+(\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda
+(_: T).(eq C c0 (CHead e1 (Bind b) u1))))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear x1 (CHead e2
+(Bind b) u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda
+(u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda
+(e1: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2)))))) (or4 (clear (CHead x1 (Flat f) x0) c0) (ex3_4 B C T T (\lambda (b:
+B).(\lambda (e: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind
+b) u1)))))) (\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2:
+T).(clear (CHead x1 (Flat f) x0) (CHead e (Bind b) u2)))))) (\lambda (_:
+B).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2))))))
+(ex3_4 B C C T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u:
+T).(eq C c0 (CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_:
+C).(\lambda (e2: C).(\lambda (u: T).(clear (CHead x1 (Flat f) x0) (CHead e2
+(Bind b) u)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda
+(_: T).(csubst0 i v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda
+(e1: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1
+(Bind b) u1))))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda
+(_: T).(\lambda (u2: T).(clear (CHead x1 (Flat f) x0) (CHead e2 (Bind b)
+u2))))))) (\lambda (_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1:
+C).(\lambda (e2: C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1
+e2)))))))) (\lambda (x3: B).(\lambda (x4: C).(\lambda (x5: C).(\lambda (x6:
+T).(\lambda (x7: T).(\lambda (H15: (eq C c0 (CHead x4 (Bind x3)
+x6))).(\lambda (H16: (clear x1 (CHead x5 (Bind x3) x7))).(\lambda (H17:
+(subst0 i v x6 x7)).(\lambda (H18: (csubst0 i v x4 x5)).(or4_intro3 (clear
+(CHead x1 (Flat f) x0) c0) (ex3_4 B C T T (\lambda (b: B).(\lambda (e:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e (Bind b) u1))))))
+(\lambda (b: B).(\lambda (e: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead x1 (Flat f) x0) (CHead e (Bind b) u2)))))) (\lambda (_: B).(\lambda
+(_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1 u2)))))) (ex3_4 B C C
+T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u: T).(eq C c0
+(CHead e1 (Bind b) u)))))) (\lambda (b: B).(\lambda (_: C).(\lambda (e2:
+C).(\lambda (u: T).(clear (CHead x1 (Flat f) x0) (CHead e2 (Bind b) u))))))
+(\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_: T).(csubst0 i
+v e1 e2)))))) (ex4_5 B C C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_:
+C).(\lambda (u1: T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind b) u1)))))))
+(\lambda (b: B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda
+(u2: T).(clear (CHead x1 (Flat f) x0) (CHead e2 (Bind b) u2))))))) (\lambda
+(_: B).(\lambda (_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2:
+T).(subst0 i v u1 u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2:
+C).(\lambda (_: T).(\lambda (_: T).(csubst0 i v e1 e2))))))) (ex4_5_intro B C
+C T T (\lambda (b: B).(\lambda (e1: C).(\lambda (_: C).(\lambda (u1:
+T).(\lambda (_: T).(eq C c0 (CHead e1 (Bind b) u1))))))) (\lambda (b:
+B).(\lambda (_: C).(\lambda (e2: C).(\lambda (_: T).(\lambda (u2: T).(clear
+(CHead x1 (Flat f) x0) (CHead e2 (Bind b) u2))))))) (\lambda (_: B).(\lambda
+(_: C).(\lambda (_: C).(\lambda (u1: T).(\lambda (u2: T).(subst0 i v u1
+u2)))))) (\lambda (_: B).(\lambda (e1: C).(\lambda (e2: C).(\lambda (_:
+T).(\lambda (_: T).(csubst0 i v e1 e2)))))) x3 x4 x5 x6 x7 H15 (clear_flat x1
+(CHead x5 (Bind x3) x7) H16 f x0) H17 H18))))))))))) H14)) H13)))))))) k H1
+H4) c2 H5)))))))) H3)) H2)))))))))))) c1).
+
+lemma csubst0_clear_trans:
+ \forall (c1: C).(\forall (c2: C).(\forall (v: T).(\forall (i: nat).((csubst0
+i v c1 c2) \to (\forall (e2: C).((clear c2 e2) \to (or (clear c1 e2) (ex2 C
+(\lambda (e1: C).(csubst0 i v e1 e2)) (\lambda (e1: C).(clear c1 e1))))))))))
+\def
+ \lambda (c1: C).(C_ind (\lambda (c: C).(\forall (c2: C).(\forall (v:
+T).(\forall (i: nat).((csubst0 i v c c2) \to (\forall (e2: C).((clear c2 e2)
+\to (or (clear c e2) (ex2 C (\lambda (e1: C).(csubst0 i v e1 e2)) (\lambda
+(e1: C).(clear c e1))))))))))) (\lambda (n: nat).(\lambda (c2: C).(\lambda
+(v: T).(\lambda (i: nat).(\lambda (H: (csubst0 i v (CSort n) c2)).(\lambda
+(e2: C).(\lambda (_: (clear c2 e2)).(csubst0_gen_sort c2 v i n H (or (clear
+(CSort n) e2) (ex2 C (\lambda (e1: C).(csubst0 i v e1 e2)) (\lambda (e1:
+C).(clear (CSort n) e1)))))))))))) (\lambda (c: C).(\lambda (H: ((\forall
+(c2: C).(\forall (v: T).(\forall (i: nat).((csubst0 i v c c2) \to (\forall
+(e2: C).((clear c2 e2) \to (or (clear c e2) (ex2 C (\lambda (e1: C).(csubst0
+i v e1 e2)) (\lambda (e1: C).(clear c e1)))))))))))).(\lambda (k: K).(\lambda
+(t: T).(\lambda (c2: C).(\lambda (v: T).(\lambda (i: nat).(\lambda (H0:
+(csubst0 i v (CHead c k t) c2)).(\lambda (e2: C).(\lambda (H1: (clear c2
+e2)).(let H2 \def (csubst0_gen_head k c c2 t v i H0) in (or3_ind (ex3_2 T nat
+(\lambda (_: T).(\lambda (j: nat).(eq nat i (s k j)))) (\lambda (u2:
+T).(\lambda (_: nat).(eq C c2 (CHead c k u2)))) (\lambda (u2: T).(\lambda (j:
+nat).(subst0 j v t u2)))) (ex3_2 C nat (\lambda (_: C).(\lambda (j: nat).(eq
+nat i (s k j)))) (\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead c3 k
+t)))) (\lambda (c3: C).(\lambda (j: nat).(csubst0 j v c c3)))) (ex4_3 T C nat
+(\lambda (_: T).(\lambda (_: C).(\lambda (j: nat).(eq nat i (s k j)))))
+(\lambda (u2: T).(\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead c3 k
+u2))))) (\lambda (u2: T).(\lambda (_: C).(\lambda (j: nat).(subst0 j v t
+u2)))) (\lambda (_: T).(\lambda (c3: C).(\lambda (j: nat).(csubst0 j v c
+c3))))) (or (clear (CHead c k t) e2) (ex2 C (\lambda (e1: C).(csubst0 i v e1
+e2)) (\lambda (e1: C).(clear (CHead c k t) e1)))) (\lambda (H3: (ex3_2 T nat
+(\lambda (_: T).(\lambda (j: nat).(eq nat i (s k j)))) (\lambda (u2:
+T).(\lambda (_: nat).(eq C c2 (CHead c k u2)))) (\lambda (u2: T).(\lambda (j:
+nat).(subst0 j v t u2))))).(ex3_2_ind T nat (\lambda (_: T).(\lambda (j:
+nat).(eq nat i (s k j)))) (\lambda (u2: T).(\lambda (_: nat).(eq C c2 (CHead
+c k u2)))) (\lambda (u2: T).(\lambda (j: nat).(subst0 j v t u2))) (or (clear
+(CHead c k t) e2) (ex2 C (\lambda (e1: C).(csubst0 i v e1 e2)) (\lambda (e1:
+C).(clear (CHead c k t) e1)))) (\lambda (x0: T).(\lambda (x1: nat).(\lambda
+(H4: (eq nat i (s k x1))).(\lambda (H5: (eq C c2 (CHead c k x0))).(\lambda
+(H6: (subst0 x1 v t x0)).(eq_ind_r nat (s k x1) (\lambda (n: nat).(or (clear
+(CHead c k t) e2) (ex2 C (\lambda (e1: C).(csubst0 n v e1 e2)) (\lambda (e1:
+C).(clear (CHead c k t) e1))))) (let H7 \def (eq_ind C c2 (\lambda (c0:
+C).(clear c0 e2)) H1 (CHead c k x0) H5) in (K_ind (\lambda (k0: K).((clear
+(CHead c k0 x0) e2) \to (or (clear (CHead c k0 t) e2) (ex2 C (\lambda (e1:
+C).(csubst0 (s k0 x1) v e1 e2)) (\lambda (e1: C).(clear (CHead c k0 t)
+e1)))))) (\lambda (b: B).(\lambda (H8: (clear (CHead c (Bind b) x0)
+e2)).(eq_ind_r C (CHead c (Bind b) x0) (\lambda (c0: C).(or (clear (CHead c
+(Bind b) t) c0) (ex2 C (\lambda (e1: C).(csubst0 (s (Bind b) x1) v e1 c0))
+(\lambda (e1: C).(clear (CHead c (Bind b) t) e1))))) (or_intror (clear (CHead
+c (Bind b) t) (CHead c (Bind b) x0)) (ex2 C (\lambda (e1: C).(csubst0 (s
+(Bind b) x1) v e1 (CHead c (Bind b) x0))) (\lambda (e1: C).(clear (CHead c
+(Bind b) t) e1))) (ex_intro2 C (\lambda (e1: C).(csubst0 (s (Bind b) x1) v e1
+(CHead c (Bind b) x0))) (\lambda (e1: C).(clear (CHead c (Bind b) t) e1))
+(CHead c (Bind b) t) (csubst0_snd (Bind b) x1 v t x0 H6 c) (clear_bind b c
+t))) e2 (clear_gen_bind b c e2 x0 H8)))) (\lambda (f: F).(\lambda (H8: (clear
+(CHead c (Flat f) x0) e2)).(or_introl (clear (CHead c (Flat f) t) e2) (ex2 C
+(\lambda (e1: C).(csubst0 (s (Flat f) x1) v e1 e2)) (\lambda (e1: C).(clear
+(CHead c (Flat f) t) e1))) (clear_flat c e2 (clear_gen_flat f c e2 x0 H8) f
+t)))) k H7)) i H4)))))) H3)) (\lambda (H3: (ex3_2 C nat (\lambda (_:
+C).(\lambda (j: nat).(eq nat i (s k j)))) (\lambda (c3: C).(\lambda (_:
+nat).(eq C c2 (CHead c3 k t)))) (\lambda (c3: C).(\lambda (j: nat).(csubst0 j
+v c c3))))).(ex3_2_ind C nat (\lambda (_: C).(\lambda (j: nat).(eq nat i (s k
+j)))) (\lambda (c3: C).(\lambda (_: nat).(eq C c2 (CHead c3 k t)))) (\lambda
+(c3: C).(\lambda (j: nat).(csubst0 j v c c3))) (or (clear (CHead c k t) e2)
+(ex2 C (\lambda (e1: C).(csubst0 i v e1 e2)) (\lambda (e1: C).(clear (CHead c
+k t) e1)))) (\lambda (x0: C).(\lambda (x1: nat).(\lambda (H4: (eq nat i (s k
+x1))).(\lambda (H5: (eq C c2 (CHead x0 k t))).(\lambda (H6: (csubst0 x1 v c
+x0)).(eq_ind_r nat (s k x1) (\lambda (n: nat).(or (clear (CHead c k t) e2)
+(ex2 C (\lambda (e1: C).(csubst0 n v e1 e2)) (\lambda (e1: C).(clear (CHead c
+k t) e1))))) (let H7 \def (eq_ind C c2 (\lambda (c0: C).(clear c0 e2)) H1
+(CHead x0 k t) H5) in (K_ind (\lambda (k0: K).((clear (CHead x0 k0 t) e2) \to
+(or (clear (CHead c k0 t) e2) (ex2 C (\lambda (e1: C).(csubst0 (s k0 x1) v e1
+e2)) (\lambda (e1: C).(clear (CHead c k0 t) e1)))))) (\lambda (b: B).(\lambda
+(H8: (clear (CHead x0 (Bind b) t) e2)).(eq_ind_r C (CHead x0 (Bind b) t)
+(\lambda (c0: C).(or (clear (CHead c (Bind b) t) c0) (ex2 C (\lambda (e1:
+C).(csubst0 (s (Bind b) x1) v e1 c0)) (\lambda (e1: C).(clear (CHead c (Bind
+b) t) e1))))) (or_intror (clear (CHead c (Bind b) t) (CHead x0 (Bind b) t))
+(ex2 C (\lambda (e1: C).(csubst0 (s (Bind b) x1) v e1 (CHead x0 (Bind b) t)))
+(\lambda (e1: C).(clear (CHead c (Bind b) t) e1))) (ex_intro2 C (\lambda (e1:
+C).(csubst0 (s (Bind b) x1) v e1 (CHead x0 (Bind b) t))) (\lambda (e1:
+C).(clear (CHead c (Bind b) t) e1)) (CHead c (Bind b) t) (csubst0_fst (Bind
+b) x1 c x0 v H6 t) (clear_bind b c t))) e2 (clear_gen_bind b x0 e2 t H8))))
+(\lambda (f: F).(\lambda (H8: (clear (CHead x0 (Flat f) t) e2)).(let H_x \def
+(H x0 v x1 H6 e2 (clear_gen_flat f x0 e2 t H8)) in (let H9 \def H_x in
+(or_ind (clear c e2) (ex2 C (\lambda (e1: C).(csubst0 x1 v e1 e2)) (\lambda
+(e1: C).(clear c e1))) (or (clear (CHead c (Flat f) t) e2) (ex2 C (\lambda
+(e1: C).(csubst0 (s (Flat f) x1) v e1 e2)) (\lambda (e1: C).(clear (CHead c
+(Flat f) t) e1)))) (\lambda (H10: (clear c e2)).(or_introl (clear (CHead c
+(Flat f) t) e2) (ex2 C (\lambda (e1: C).(csubst0 (s (Flat f) x1) v e1 e2))
+(\lambda (e1: C).(clear (CHead c (Flat f) t) e1))) (clear_flat c e2 H10 f
+t))) (\lambda (H10: (ex2 C (\lambda (e1: C).(csubst0 x1 v e1 e2)) (\lambda
+(e1: C).(clear c e1)))).(ex2_ind C (\lambda (e1: C).(csubst0 x1 v e1 e2))
+(\lambda (e1: C).(clear c e1)) (or (clear (CHead c (Flat f) t) e2) (ex2 C
+(\lambda (e1: C).(csubst0 (s (Flat f) x1) v e1 e2)) (\lambda (e1: C).(clear
+(CHead c (Flat f) t) e1)))) (\lambda (x: C).(\lambda (H11: (csubst0 x1 v x
+e2)).(\lambda (H12: (clear c x)).(or_intror (clear (CHead c (Flat f) t) e2)
+(ex2 C (\lambda (e1: C).(csubst0 (s (Flat f) x1) v e1 e2)) (\lambda (e1:
+C).(clear (CHead c (Flat f) t) e1))) (ex_intro2 C (\lambda (e1: C).(csubst0
+(s (Flat f) x1) v e1 e2)) (\lambda (e1: C).(clear (CHead c (Flat f) t) e1)) x
+H11 (clear_flat c x H12 f t)))))) H10)) H9))))) k H7)) i H4)))))) H3))
+(\lambda (H3: (ex4_3 T C nat (\lambda (_: T).(\lambda (_: C).(\lambda (j:
+nat).(eq nat i (s k j))))) (\lambda (u2: T).(\lambda (c3: C).(\lambda (_:
+nat).(eq C c2 (CHead c3 k u2))))) (\lambda (u2: T).(\lambda (_: C).(\lambda
+(j: nat).(subst0 j v t u2)))) (\lambda (_: T).(\lambda (c3: C).(\lambda (j:
+nat).(csubst0 j v c c3)))))).(ex4_3_ind T C nat (\lambda (_: T).(\lambda (_:
+C).(\lambda (j: nat).(eq nat i (s k j))))) (\lambda (u2: T).(\lambda (c3:
+C).(\lambda (_: nat).(eq C c2 (CHead c3 k u2))))) (\lambda (u2: T).(\lambda
+(_: C).(\lambda (j: nat).(subst0 j v t u2)))) (\lambda (_: T).(\lambda (c3:
+C).(\lambda (j: nat).(csubst0 j v c c3)))) (or (clear (CHead c k t) e2) (ex2
+C (\lambda (e1: C).(csubst0 i v e1 e2)) (\lambda (e1: C).(clear (CHead c k t)
+e1)))) (\lambda (x0: T).(\lambda (x1: C).(\lambda (x2: nat).(\lambda (H4: (eq
+nat i (s k x2))).(\lambda (H5: (eq C c2 (CHead x1 k x0))).(\lambda (H6:
+(subst0 x2 v t x0)).(\lambda (H7: (csubst0 x2 v c x1)).(eq_ind_r nat (s k x2)
+(\lambda (n: nat).(or (clear (CHead c k t) e2) (ex2 C (\lambda (e1:
+C).(csubst0 n v e1 e2)) (\lambda (e1: C).(clear (CHead c k t) e1))))) (let H8
+\def (eq_ind C c2 (\lambda (c0: C).(clear c0 e2)) H1 (CHead x1 k x0) H5) in
+(K_ind (\lambda (k0: K).((clear (CHead x1 k0 x0) e2) \to (or (clear (CHead c
+k0 t) e2) (ex2 C (\lambda (e1: C).(csubst0 (s k0 x2) v e1 e2)) (\lambda (e1:
+C).(clear (CHead c k0 t) e1)))))) (\lambda (b: B).(\lambda (H9: (clear (CHead
+x1 (Bind b) x0) e2)).(eq_ind_r C (CHead x1 (Bind b) x0) (\lambda (c0: C).(or
+(clear (CHead c (Bind b) t) c0) (ex2 C (\lambda (e1: C).(csubst0 (s (Bind b)
+x2) v e1 c0)) (\lambda (e1: C).(clear (CHead c (Bind b) t) e1))))) (or_intror
+(clear (CHead c (Bind b) t) (CHead x1 (Bind b) x0)) (ex2 C (\lambda (e1:
+C).(csubst0 (s (Bind b) x2) v e1 (CHead x1 (Bind b) x0))) (\lambda (e1:
+C).(clear (CHead c (Bind b) t) e1))) (ex_intro2 C (\lambda (e1: C).(csubst0
+(s (Bind b) x2) v e1 (CHead x1 (Bind b) x0))) (\lambda (e1: C).(clear (CHead
+c (Bind b) t) e1)) (CHead c (Bind b) t) (csubst0_both (Bind b) x2 v t x0 H6 c
+x1 H7) (clear_bind b c t))) e2 (clear_gen_bind b x1 e2 x0 H9)))) (\lambda (f:
+F).(\lambda (H9: (clear (CHead x1 (Flat f) x0) e2)).(let H_x \def (H x1 v x2
+H7 e2 (clear_gen_flat f x1 e2 x0 H9)) in (let H10 \def H_x in (or_ind (clear
+c e2) (ex2 C (\lambda (e1: C).(csubst0 x2 v e1 e2)) (\lambda (e1: C).(clear c
+e1))) (or (clear (CHead c (Flat f) t) e2) (ex2 C (\lambda (e1: C).(csubst0 (s
+(Flat f) x2) v e1 e2)) (\lambda (e1: C).(clear (CHead c (Flat f) t) e1))))
+(\lambda (H11: (clear c e2)).(or_introl (clear (CHead c (Flat f) t) e2) (ex2
+C (\lambda (e1: C).(csubst0 (s (Flat f) x2) v e1 e2)) (\lambda (e1: C).(clear
+(CHead c (Flat f) t) e1))) (clear_flat c e2 H11 f t))) (\lambda (H11: (ex2 C
+(\lambda (e1: C).(csubst0 x2 v e1 e2)) (\lambda (e1: C).(clear c
+e1)))).(ex2_ind C (\lambda (e1: C).(csubst0 x2 v e1 e2)) (\lambda (e1:
+C).(clear c e1)) (or (clear (CHead c (Flat f) t) e2) (ex2 C (\lambda (e1:
+C).(csubst0 (s (Flat f) x2) v e1 e2)) (\lambda (e1: C).(clear (CHead c (Flat
+f) t) e1)))) (\lambda (x: C).(\lambda (H12: (csubst0 x2 v x e2)).(\lambda
+(H13: (clear c x)).(or_intror (clear (CHead c (Flat f) t) e2) (ex2 C (\lambda
+(e1: C).(csubst0 (s (Flat f) x2) v e1 e2)) (\lambda (e1: C).(clear (CHead c
+(Flat f) t) e1))) (ex_intro2 C (\lambda (e1: C).(csubst0 (s (Flat f) x2) v e1
+e2)) (\lambda (e1: C).(clear (CHead c (Flat f) t) e1)) x H12 (clear_flat c x
+H13 f t)))))) H11)) H10))))) k H8)) i H4)))))))) H3)) H2)))))))))))) c1).
+