(** The function [(Z.pow_pos z)] is a morphism for [Pos.add : positive->positive->positive] and [Z.mul : Z->Z->Z] *)

(* Specifications: *)
Lemma Zpower_pos_is_exp (n m : positive)(z:Z) :
Z.pow_pos z (n + m) = Z.pow_pos z n * Z.pow_pos z m.