(* Specific properties on at ************************************************)
-lemma at_O1: â\88\80i2,f. @â¦\830, i2@fâ¦\84 â\89¡ i2.
+lemma at_O1: â\88\80i2,f. @â¦\830, i2@fâ¦\84 â\89\98 i2.
#i2 elim i2 -i2 /2 width=5 by at_refl, at_next/
qed.
-lemma at_S1: â\88\80n,f,i1,i2. @â¦\83i1, fâ¦\84 â\89¡ i2 â\86\92 @â¦\83⫯i1, n@fâ¦\84 â\89¡ ⫯(n+i2).
+lemma at_S1: â\88\80n,f,i1,i2. @â¦\83i1, fâ¦\84 â\89\98 i2 â\86\92 @â¦\83⫯i1, n@fâ¦\84 â\89\98 ⫯(n+i2).
#n elim n -n /3 width=7 by at_push, at_next/
qed.
-lemma at_total: â\88\80i1,f. @â¦\83i1, fâ¦\84 â\89¡ f@❴i1❵.
+lemma at_total: â\88\80i1,f. @â¦\83i1, fâ¦\84 â\89\98 f@❴i1❵.
#i1 elim i1 -i1
[ * // | #i #IH * /3 width=1 by at_S1/ ]
qed.
lemma at_istot: ∀f. 𝐓⦃f⦄.
/2 width=2 by ex_intro/ qed.
-lemma at_plus2: â\88\80f,i1,i,n,m. @â¦\83i1, n@fâ¦\84 â\89¡ i â\86\92 @â¦\83i1, (m+n)@fâ¦\84 â\89¡ m+i.
+lemma at_plus2: â\88\80f,i1,i,n,m. @â¦\83i1, n@fâ¦\84 â\89\98 i â\86\92 @â¦\83i1, (m+n)@fâ¦\84 â\89\98 m+i.
#f #i1 #i #n #m #H elim m -m //
#m <plus_S1 /2 width=5 by at_next/ (**) (* full auto fails *)
qed.
(* Specific inversion lemmas on at ******************************************)
-lemma at_inv_O1: â\88\80f,n,i2. @â¦\830, n@fâ¦\84 â\89¡ i2 → n = i2.
+lemma at_inv_O1: â\88\80f,n,i2. @â¦\830, n@fâ¦\84 â\89\98 i2 → n = i2.
#f #n elim n -n /2 width=6 by at_inv_ppx/
#n #IH #i2 #H elim (at_inv_xnx … H) -H [2,3: // ]
#j2 #Hj * -i2 /3 width=1 by eq_f/
qed-.
-lemma at_inv_S1: â\88\80f,n,j1,i2. @â¦\83⫯j1, n@fâ¦\84 â\89¡ i2 →
- â\88\83â\88\83j2. @â¦\83j1, fâ¦\84 â\89¡ j2 & ⫯(n+j2) = i2.
+lemma at_inv_S1: â\88\80f,n,j1,i2. @â¦\83⫯j1, n@fâ¦\84 â\89\98 i2 →
+ â\88\83â\88\83j2. @â¦\83j1, fâ¦\84 â\89\98 j2 & ⫯(n+j2) = i2.
#f #n elim n -n /2 width=5 by at_inv_npx/
#n #IH #j1 #i2 #H elim (at_inv_xnx … H) -H [2,3: // ]
#j2 #Hj * -i2 elim (IH … Hj) -IH -Hj
#i2 #Hi * -j2 /2 width=3 by ex2_intro/
qed-.
-lemma at_inv_total: â\88\80f,i1,i2. @â¦\83i1, fâ¦\84 â\89¡ i2 → f@❴i1❵ = i2.
+lemma at_inv_total: â\88\80f,i1,i2. @â¦\83i1, fâ¦\84 â\89\98 i2 → f@❴i1❵ = i2.
/2 width=6 by at_mono/ qed-.
(* Spercific forward lemmas on at *******************************************)
-lemma at_increasing_plus: â\88\80f,n,i1,i2. @â¦\83i1, n@fâ¦\84 â\89¡ i2 → i1 + n ≤ i2.
+lemma at_increasing_plus: â\88\80f,n,i1,i2. @â¦\83i1, n@fâ¦\84 â\89\98 i2 → i1 + n ≤ i2.
#f #n *
[ #i2 #H <(at_inv_O1 … H) -i2 //
| #i1 #i2 #H elim (at_inv_S1 … H) -H
]
qed-.
-lemma at_fwd_id: â\88\80f,n,i. @â¦\83i, n@fâ¦\84 â\89¡ i → 0 = n.
+lemma at_fwd_id: â\88\80f,n,i. @â¦\83i, n@fâ¦\84 â\89\98 i → 0 = n.
#f #n #i #H elim (at_fwd_id_ex … H) -H
#g #H elim (push_inv_seq_dx … H) -H //
qed-.