]> matita.cs.unibo.it Git - helm.git/blobdiff - matita/matita/contribs/lambdadelta/ground/arith/nat_pred_succ.ma
update in ground
[helm.git] / matita / matita / contribs / lambdadelta / ground / arith / nat_pred_succ.ma
index ac01f0f8fc3aefbf78466e018ea478e8db5840f4..3d79e371ebb0561e12510868a5af77df236c3868 100644 (file)
@@ -24,10 +24,10 @@ lemma npred_succ (n): n = ↓↑n.
 * //
 qed.
 
-(* Inversion with nsucc *****************************************************)
+(* Inversions with nsucc ****************************************************)
 
 (*** nat_split *)
-lemma nat_split (n): ∨∨ 𝟎 = n | n = ↑↓n.
+lemma nat_split_zero_pos (n): ∨∨ 𝟎 = n | n = ↑↓n.
 #n @(nat_ind_succ … n) -n
 /2 width=1 by or_introl, or_intror/
 qed-.