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(* 02110-1301 USA                                                     *)
(** modprime. Some nice lemmas about div, mult, mod, prime, and gcd.  @author Olga Caprotti and Martijn Oostdijk @version $Revision$ *)

Lemma mod_mult_inv_r :
forall (a : Z) (p : nat),
Prime p -> ~ Mod a 0 p -> exists ra : Z, Mod (a * ra) 1 p.