X-Git-Url: http://matita.cs.unibo.it/gitweb/?p=helm.git;a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fground%2Farith%2Fnat_minus_plus.ma;h=bf5cf5fee5833a7cf22086fbb01a967eeb8c49a9;hp=47e88de49c8255b43a76102bd60b7f51534553fb;hb=ccf5878f2a2ec7f952f140e162391708a740517b;hpb=5e72e41f4f86814e56d4b00959ccc56c71042a4c

diff --git a/matita/matita/contribs/lambdadelta/ground/arith/nat_minus_plus.ma b/matita/matita/contribs/lambdadelta/ground/arith/nat_minus_plus.ma
index 47e88de49..bf5cf5fee 100644
--- a/matita/matita/contribs/lambdadelta/ground/arith/nat_minus_plus.ma
+++ b/matita/matita/contribs/lambdadelta/ground/arith/nat_minus_plus.ma
@@ -30,14 +30,14 @@ lemma nminus_plus_sn_refl_dx (m) (n): m = n + m - n.
 qed.
 
 (*** minus_plus *)
-theorem nminus_assoc (o) (m) (n): o-m-n = o-(m+n).
+theorem nminus_plus_assoc (o) (m) (n): o-m-n = o-(m+n).
 #o #m #n elim n -n //
 #n #IH <nplus_succ_dx <nminus_succ_dx <nminus_succ_dx //
 qed-.
 
 (*** minus_plus_plus_l *)
 lemma nminus_plus_dx_bi (m) (n) (o): m - n = (m + o) - (n + o).
-#m #n #o <nminus_assoc <nminus_minus_comm //
+#m #n #o <nminus_plus_assoc <nminus_minus_comm //
 qed.
 
 (*** plus_minus_plus_plus_l *) (**)