fact: Definition pr1_dni_lastelement {n : nat} {i: ⟦n⟧ } : pr1 (dni_lastelement i) = pr1 i.
imports: UniMath.Foundations.NaturalNumbers UniMath.MoreFoundations.Tactics UniMath.MoreFoundations.DecidablePropositions UniMath.MoreFoundations.NegativePropositions