intros Q p q H'; inversion H'; auto.
Qed.

Theorem reducestar_irreducible :
forall (Q : list (poly A0 eqA ltM)) (p q : list (Term A n)),
reducestar Q p q ->
irreducible A A0 A1 eqA invA minusA multA divA eqA_dec n ltM ltM_dec Q q.