fact: CoInductive eqone : inftree -> Prop := | eqone_fold tl tr (EQL : eqone tl : Prop) (EQR : eqtwo tr : Prop): eqone (node 1 tl tr) with eqtwo : inftree -> Prop := | eqtwo_fold tl tr (EQL : eqone tl : Prop) (EQR : eqtwo tr : Prop): eqtwo (node 2 tl tr).
imports: Setoid Program Paco.paco