(* Main properties **********************************************************)
(* Basic_1: was: lifts1_xhg (right to left) *)
-lemma liftsv_liftv_trans_le: â\88\80T1s,Ts,des. â\87§*[des] T1s ≡ Ts →
- â\88\80T2s:list term. â\87§[0, 1] Ts ≡ T2s →
- â\88\83â\88\83T0s. â\87§[0, 1] T1s â\89¡ T0s & â\87§*[des + 1] T0s ≡ T2s.
+lemma liftsv_liftv_trans_le: â\88\80T1s,Ts,des. â¬\86*[des] T1s ≡ Ts →
+ â\88\80T2s:list term. â¬\86[0, 1] Ts ≡ T2s →
+ â\88\83â\88\83T0s. â¬\86[0, 1] T1s â\89¡ T0s & â¬\86*[des + 1] T0s ≡ T2s.
#T1s #Ts #des #H elim H -T1s -Ts
[ #T1s #H
>(liftv_inv_nil1 … H) -T1s /2 width=3/