intros aP R Q H'; elim H'; simpl in |- *; auto.
intros; apply red_cons with (1 := cs); auto.
Qed.

(* Specifications: *)
Theorem ObuchQred :
forall aP R Q : list (poly A0 eqA ltM),
OBuch aP Q R ->
forall a : poly A0 eqA ltM,
In a Q -> red A A0 A1 eqA invA minusA multA divA eqA_dec n ltM ltM_dec a R.