X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fbasic_2%2Fsubstitution%2Flsuby.ma;h=578612a71b8c5b2688858b264027d1ec55d9f9a6;hb=6f1f9e20aa2775d41bba64289fc903e6612baaf3;hp=73f35cdd2ddecc38edc915f208f2f2a8e04e29f9;hpb=52e675f555f559c047d5449db7fc89a51b977d35;p=helm.git

diff --git a/matita/matita/contribs/lambdadelta/basic_2/substitution/lsuby.ma b/matita/matita/contribs/lambdadelta/basic_2/substitution/lsuby.ma
index 73f35cdd2..578612a71 100644
--- a/matita/matita/contribs/lambdadelta/basic_2/substitution/lsuby.ma
+++ b/matita/matita/contribs/lambdadelta/basic_2/substitution/lsuby.ma
@@ -210,9 +210,9 @@ qed-.
 (* Properties on basic slicing **********************************************)
 
 lemma lsuby_drop_trans_be: ∀L1,L2,d,e. L1 ⊆[d, e] L2 →
-                           ∀I2,K2,W,s,i. ⇩[s, 0, i] L2 ≡ K2.ⓑ{I2}W →
+                           ∀I2,K2,W,s,i. ⬇[s, 0, i] L2 ≡ K2.ⓑ{I2}W →
                            d ≤ i → i < d + e →
-                           ∃∃I1,K1. K1 ⊆[0, ⫰(d+e-i)] K2 & ⇩[s, 0, i] L1 ≡ K1.ⓑ{I1}W.
+                           ∃∃I1,K1. K1 ⊆[0, ⫰(d+e-i)] K2 & ⬇[s, 0, i] L1 ≡ K1.ⓑ{I1}W.
 #L1 #L2 #d #e #H elim H -L1 -L2 -d -e
 [ #L1 #d #e #J2 #K2 #W #s #i #H
   elim (drop_inv_atom1 … H) -H #H destruct