proposition: Theorem bi_induction : forall A : nat -> Prop, Proper (eq==>iff) A -> A 0 -> (forall n : nat, A n <-> A (S n)) -> forall n : nat, A n.
proof: Proof. intros A A_wd A0 AS; apply nat_ind. - assumption. - intros; now apply -> AS. Qed.
imports: NAxioms NProperties OrdersFacts DecidableClass