Fixpoint power_later (n:nat) P :=
    match n with
    | 0%nat => P
    | S n' => later (power_later n' P)
    end
.

(* Specifications: *)
Lemma power_later_andp: forall (n:nat) (P Q : mpred), power_later n (P && Q) = (power_later n P) && (power_later n Q).
Lemma power_later_sepcon: forall n P Q, power_later n (P * Q) = (power_later n P) * (power_later n Q).
Lemma power_later_TT: forall n, TT = power_later n TT.
Lemma corable_power_later: forall n P, corable P -> corable (power_later n P).