X-Git-Url: http://matita.cs.unibo.it/gitweb/?p=helm.git;a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fground_2%2Fsteps%2Frtc_ist.ma;h=4b4c8ac8fcf4d8812f2e38a6b9bb899ca4e08cc6;hp=6b9b64681e4372887e234a10d5ac16ba21fae63a;hb=f38fd769279794d0ca73c8945eac30e8b42e59be;hpb=0af3592e3a85a4bb82c5c6df259cf9ab117ba0b1

diff --git a/matita/matita/contribs/lambdadelta/ground_2/steps/rtc_ist.ma b/matita/matita/contribs/lambdadelta/ground_2/steps/rtc_ist.ma
index 6b9b64681..4b4c8ac8f 100644
--- a/matita/matita/contribs/lambdadelta/ground_2/steps/rtc_ist.ma
+++ b/matita/matita/contribs/lambdadelta/ground_2/steps/rtc_ist.ma
@@ -41,6 +41,10 @@ lemma ist_inv_01: ∀n. 𝐓⦃n,𝟘𝟙⦄ → 1 = n.
 #n #H destruct //
 qed-.
 
+lemma ist_inv_10: ∀n. 𝐓⦃n,𝟙𝟘⦄ → ⊥.
+#h #H destruct
+qed-.
+
 (* Main inversion properties ************************************************)
 
 theorem ist_inj: ∀n1,n2,c. 𝐓⦃n1,c⦄ → 𝐓⦃n2,c⦄ → n1 = n2.