fact: Definition Tr (x y : nat * (nat * unit)) : Prop := (fst x = fst (snd y) /\ fst (snd x) < fst y).
imports: Equations(Equations) Examples.Fin Relations Utf8 Relations Wellfounded Setoid RelationClasses Morphisms Lia Bool List Arith String Coq(FunctionalExtensionality)