proposition: Lemma gpaco12_unfold clo r rg: gpaco12 clo r rg <12= rclo12 clo (gf (gupaco12 clo (rg \12/ r)) \12/ r).
proof: Proof. intros. destruct PR. eapply rclo12_mon. apply IN. intros. destruct PR; cycle 1. right; apply H. left. _punfold H; [|apply gpaco12_def_mon]. eapply gf_mon. apply H. intros. econstructor. eapply rclo12_mon. apply PR. intros. destruct PR0; cycle 1. right. apply H0. left. eapply paco12_mon. apply H0. intros. left. apply PR0. Qed.
imports: Program.Basics Paco(paco12 pacotac)