proposition: Lemma finset_fixpoint_eq: forall F M, finset_eq (finset_fixpoint F M) (F (finset_fixpoint F M)).
proof: Proof. intros. unfold finset_fixpoint. apply fixpoint_eq. Qed.
imports: Coq(ZArith Psatz Bool String Program.Equality FSets Wellfounded) CDF(Sequences IMP Simulation) CDF(Fixpoints)