proposition: Lemma neghfiberdni ( n : nat ) ( i : ⟦S n⟧ ) : ¬ ( hfiber ( dni i ) i ).
proof: Proof. intros. apply ( negf ( weqhfiberdnihfiberdi n i i ) ( neghfiberdi i ) ). Defined.
imports: UniMath.Foundations.NaturalNumbers UniMath.MoreFoundations.Tactics UniMath.MoreFoundations.DecidablePropositions UniMath.MoreFoundations.NegativePropositions