proposition: Lemma gcdand0 ( n : hz ) ( i : hzneq 0 n ) : ( gcd n 0 i = n ) ⨿ ( gcd n 0 i = - n ).
proof: Proof. intros. apply gcdanddiv. apply hzdivand0. Defined.
imports: UniMath.PAdics.lemmas UniMath.NumberSystems.Integers UniMath.Foundations.Preamble