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14
15 set "baseuri" "cic:/matita/RELATIONAL/Nat/fwd".
16
17 include "logic/equality.ma".
18
19 include "Nat/defs.ma".
20
21 theorem eq_gen_zero_succ: \forall m2. zero = succ m2 \to False.
22  intros. destruct H.
23 qed.
24
25 theorem eq_gen_succ_zero: \forall m1. succ m1 = zero \to False.
26  intros. destruct H.
27 qed.
28
29 theorem eq_gen_succ_succ: \forall m1,m2. succ m1 = succ m2 \to m1 = m2.
30  intros. destruct H. assumption.
31 qed.