proposition: Lemma well_formed_cf_sorted : forall f l, arity f = AC -> well_formed_cf (Term f l) -> is_sorted l.
proof: Proof. intros f l Af [_ Ll]; rewrite Af in Ll; intuition. Qed.
imports: Coq(Relations List Arith Morphisms) CoLoR(more_list list_permut list_sort term_spec term_o equational_theory_spec equational_theory)