proposition: Lemma acc_with_subterm_subterms : forall R t, Acc (union _ (one_step R) direct_subterm) t -> forall s, direct_subterm s t -> Acc (union _ (one_step R) direct_subterm) s.
proof: Proof. intros R t Acc_t; induction Acc_t as [t Acc_t IH]. intros s H; apply Acc_t; right; trivial. Qed.
imports: Coq(List Relations Wellfounded Arith Setoid) CoLoR(closure more_list weaved_relation dickson term_spec equational_theory_spec)