intros; elim (tech_mult_pos_succZ n m).
simpl in |- *; elim (mult_n_Sm n m); elim (plus_assoc m (n * m) n);
reflexivity.
Qed.

(**************)
Lemma tech_div1 :
forall n0 n q r : nat,
S n0 = q * S n + r -> pos n0 = addZ (multZ (pos n) (posOZ q)) (posOZ r).