proposition: Lemma hzeqeissi {i i0 : hz} (e : hzeq i i0) (e' : hzeq i (i0 + 1 + 1)) : empty.
proof: Proof. cbn in e. rewrite e in e'. apply (hzeqissi e'). Qed.
imports: UniMath.Foundations.NaturalNumbers UniMath.MoreFoundations.PartA UniMath.MoreFoundations.NegativePropositions UniMath.Algebra.Monoids UniMath.Algebra.Groups UniMath.Algebra.RigsAndRings UniMath.NumberSystems.NaturalNumbersAlgebra