proposition: Lemma axEUeq (s t : form) : prv (EU s t <--> t :\/: s :/\: EX (EU s t)).
proof: Proof. exact: axEUeq. Qed.
imports: mathcomp.ssreflect.ssreflect mathcomp(all_ssreflect) CompDecModal.libs(edone bcase fset base modular_hilbert) CompDecModal.CTL(CTL_def hilbert)