intros n; elim n; clear n; auto.
intros p q; try rewrite <- Zplus_0_r_reverse.
intros H' H'0; simpl in |- *; left.
apply Zle_antisym; auto.
intros n H' p q H'0 H'1; case (Zle_lt_or_eq _ _ H'0); intros H'2.
simpl in |- *; right.
apply H'; auto with zarith.
rewrite Zplus_succ_comm.
rewrite <- inj_S; auto.
simpl in |- *; auto.
Qed.

(* Specifications: *)
Theorem mZlist_aux_correct_rev1 :
forall (n : nat) (p q : Z), In q (mZlist_aux p n) -> (p <= q)%Z.