fact: Definition t k := ⟨enc (k * n) A, enc k B⟩.
imports: List Lia Program.Program Undecidability.HOU(std.std axioms) RelationClasses Morphisms Init.Wf Init.Nat Setoid Undecidability.HOU(calculus.calculus second_order.goldfarb.encoding) FinFun Coq.Arith.Wf_nat