eapply OTP_inf_th_sec_l; intuition.
apply associativity.
eapply left_inverse.
eapply right_inverse.
eapply left_identity.
eapply RndGrpElem_spec.
Qed.

(* Specifications: *)
Theorem group_OTP_r :
forall (x : GroupElement),
comp_spec eq (RndG) (r <-$ RndG; ret (groupOp r x)).