(* *)
(**************************************************************************)
+include "ground_2/ynat/ynat_max.ma".
include "basic_2/substitution/lift_lift.ma".
include "basic_2/multiple/mr2_minus.ma".
include "basic_2/multiple/lifts.ma".
∀T1,T0. ⬆*[cs0] T1 ≡ T0 →
∀T2. ⬆[O, i0 + 1] T0 ≡ T2 →
∃∃T. ⬆[0, i + 1] T1 ≡ T & ⬆*[cs] T ≡ T2.
-#cs elim cs -cs normalize
+#cs elim cs -cs
[ #i #x #H1 #cs0 #H2 #T1 #T0 #HT10 #T2
<(at_inv_nil … H1) -x #HT02
lapply (minuss_inv_nil1 … H2) -H2 #H
>(lifts_inv_nil … H) -T1 /2 width=3 by lifts_nil, ex2_intro/
| #l #m #cs #IHcs #i #i0 #H1 #cs0 #H2 #T1 #T0 #HT10 #T2 #HT02
elim (at_inv_cons … H1) -H1 * #Hil #Hi0
- [ elim (minuss_inv_cons1_lt … H2) -H2 [2: /2 width=1 by lt_minus_to_plus/ ] #cs1 #Hcs1 <minus_le_minus_minus_comm // <minus_plus_m_m #H
+ [ elim (minuss_inv_cons1_lt … H2) -H2 /2 width=1 by ylt_succ/ #cs1 #Hcs1
+ <yplus_inj >yplus_SO2 >yplus_SO2 >yminus_succ #H
elim (pluss_inv_cons2 … H) -H #cs2 #H1 #H2 destruct
- elim (lifts_inv_cons … HT10) -HT10 #T >minus_plus #HT1 #HT0
+ elim (lifts_inv_cons … HT10) -HT10 #T #HT1 #HT0
elim (IHcs … Hi0 … Hcs1 … HT0 … HT02) -IHcs -Hi0 -Hcs1 -T0 #T0 #HT0 #HT02
- elim (lift_trans_le … HT1 … HT0) -T /2 width=1 by/ #T #HT1 <plus_minus_m_m /3 width=5 by lifts_cons, ex2_intro/
+ elim (lift_trans_le … HT1 … HT0) -T /2 width=1 by/ #T #HT1
+ <yminus_plus2 <yplus_inj >yplus_SO2 >ymax_pre_sn
+ /3 width=5 by lifts_cons, ex2_intro, ylt_fwd_le_succ1/
| >commutative_plus in Hi0; #Hi0
- lapply (minuss_inv_cons1_ge … H2 ?) -H2 [ /2 width=1 by le_S_S/ ] <associative_plus #Hcs0
+ lapply (minuss_inv_cons1_ge … H2 ?) -H2 /2 width=1 by yle_succ/ <associative_plus #Hcs0
elim (IHcs … Hi0 … Hcs0 … HT10 … HT02) -IHcs -Hi0 -Hcs0 -T0 #T0 #HT0 #HT02
- elim (lift_split … HT0 l (i+1)) -HT0 /3 width=5 by lifts_cons, le_S, ex2_intro/
+ elim (lift_split … HT0 l (i+1)) -HT0 /3 width=5 by lifts_cons, yle_succ, yle_pred_sn, ex2_intro/
]
]
qed-.