proposition: Theorem OMH_G2_equiv: Pr[OMH_G2] == Pr[G2 _ O2 A1 OMH_G_oc].
proof: Proof. unfold OMH_G2. rewrite OMH_G_oc_equiv. unfold G2, OMH_G_oc. reflexivity. Qed.
imports: FCF.FCF FCF.RndInList FCF.CompFold FCF.OracleCompFold FCF.PRF