proposition: Theorem stable_sym : forall Q R : list (poly A0 eqA ltM), stable R Q -> stable Q R.
proof: Proof. intros Q R H'; elim H'; auto. Qed.
imports: Coq(Arith Inclusion Inverse_Image Wf_nat Relation_Definitions) Coq(Relation_Operators Lexicographic_Product) Buchberger(Relation_Operators_compat LetP)