proposition: Lemma gpaco3_dist_reverse clo r rg: (paco3 gf (rclo3 clo (rg \3/ r)) \3/ rclo3 clo r) <3= gpaco3 gf clo r rg.
proof: Proof. intros. destruct PR; cycle 1. - eapply gpaco3_rclo. apply H. - econstructor. apply rclo3_base. left. revert x0 x1 x2 H. pcofix CIH; intros. _punfold H0; [|apply gf_mon]. pstep. eapply gf_mon. apply H0. intros. destruct PR. + apply rclo3_base. right. apply CIH, H. + eapply rclo3_mon. apply H. intros. right. apply CIH0. apply PR. Qed.
imports: Program.Basics Paco(paco3 pacotac)