proposition: Lemma iter_add : forall p q (A:Type) (f:A -> A) (x:A), iter (p+q) f x = iter p f (iter q f x).
proof: Proof. intro p. induction p as [|p IHp]. - reflexivity. - intros q A f x. simpl. now rewrite IHp. Qed.
imports: NAxioms NProperties OrdersFacts DecidableClass