X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fbasic_2%2Fstatic%2Flfdeq_drops.ma;h=f77f0a0ffbaf956659f915a831c406a8a3cfff12;hb=6167cca50de37eba76a062537b24f7caef5b34f2;hp=4b8f2f92bda4d1e06d9f38e220045753755f8687;hpb=6d49221c1fefe6a2c5bddb3db24d3698414a700f;p=helm.git

diff --git a/matita/matita/contribs/lambdadelta/basic_2/static/lfdeq_drops.ma b/matita/matita/contribs/lambdadelta/basic_2/static/lfdeq_drops.ma
index 4b8f2f92b..f77f0a0ff 100644
--- a/matita/matita/contribs/lambdadelta/basic_2/static/lfdeq_drops.ma
+++ b/matita/matita/contribs/lambdadelta/basic_2/static/lfdeq_drops.ma
@@ -33,15 +33,15 @@ lemma lfdeq_inv_lifts_dx: ∀h,o. dropable_dx (cdeq h o).
 /2 width=5 by lfxs_dropable_dx/ qed-.
 
 (* Basic_2A1: uses: lleq_inv_lift_le lleq_inv_lift_be lleq_inv_lift_ge *)
-lemma lfdeq_inv_lifts_bi: ∀h,o,L1,L2,U. L1 ≡[h, o, U] L2 → ∀b,f. 𝐔⦃f⦄ →
+lemma lfdeq_inv_lifts_bi: ∀h,o,L1,L2,U. L1 ≛[h, o, U] L2 → ∀b,f. 𝐔⦃f⦄ →
                           ∀K1,K2. ⬇*[b, f] L1 ≡ K1 → ⬇*[b, f] L2 ≡ K2 →
-                          ∀T. ⬆*[f] T ≡ U → K1 ≡[h, o, T] K2.
+                          ∀T. ⬆*[f] T ≡ U → K1 ≛[h, o, T] K2.
 /2 width=10 by lfxs_inv_lifts_bi/ qed-.
 
-lemma lfdeq_inv_lref_pair_sn: ∀h,o,L1,L2,i. L1 ≡[h, o, #i] L2 → ∀I,K1,V1. ⬇*[i] L1 ≡ K1.ⓑ{I}V1 →
-                              ∃∃K2,V2. ⬇*[i] L2 ≡ K2.ⓑ{I}V2 & K1 ≡[h, o, V1] K2 & V1 ≡[h, o] V2.
+lemma lfdeq_inv_lref_pair_sn: ∀h,o,L1,L2,i. L1 ≛[h, o, #i] L2 → ∀I,K1,V1. ⬇*[i] L1 ≡ K1.ⓑ{I}V1 →
+                              ∃∃K2,V2. ⬇*[i] L2 ≡ K2.ⓑ{I}V2 & K1 ≛[h, o, V1] K2 & V1 ≛[h, o] V2.
 /2 width=3 by lfxs_inv_lref_pair_sn/ qed-.
 
-lemma lfdeq_inv_lref_pair_dx: ∀h,o,L1,L2,i. L1 ≡[h, o, #i] L2 → ∀I,K2,V2. ⬇*[i] L2 ≡ K2.ⓑ{I}V2 →
-                              ∃∃K1,V1. ⬇*[i] L1 ≡ K1.ⓑ{I}V1 & K1 ≡[h, o, V1] K2 & V1 ≡[h, o] V2.
+lemma lfdeq_inv_lref_pair_dx: ∀h,o,L1,L2,i. L1 ≛[h, o, #i] L2 → ∀I,K2,V2. ⬇*[i] L2 ≡ K2.ⓑ{I}V2 →
+                              ∃∃K1,V1. ⬇*[i] L1 ≡ K1.ⓑ{I}V1 & K1 ≛[h, o, V1] K2 & V1 ≛[h, o] V2.
 /2 width=3 by lfxs_inv_lref_pair_dx/ qed-.