Instance eqm_setoid : Equivalence eqm.Instance Zplus_eqm : Proper (eqm ==> eqm ==> eqm) Z.add.Instance Zminus_eqm : Proper (eqm ==> eqm ==> eqm) Z.sub.Instance Zmult_eqm : Proper (eqm ==> eqm ==> eqm) Z.mul.Instance Zopp_eqm : Proper (eqm ==> eqm) Z.opp.

Lemma Z_mod_plus : forall a b c:Z, c > 0 -> (a + b * c) mod c = a mod c.