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(* 02110-1301 USA                                                     *)
(** modulo Modulo Arithmetic.  @author Olga Caprotti and Martijn Oostdijk @version $Revision$ *)
(** (Mod a b n) means (a = b (mod n)) *)
Definition Mod (a b : Z) (n : nat) :=
exists q : Z, a = (b + Z_of_nat n * q)%Z.

Lemma mod_exp_compat :
forall (a b : Z) (n : nat),
Mod a b n -> forall m : nat, Mod (Exp a m) (Exp b m) n.