fact: Variables (Σ : finType) (M : TM Σ 1) (ts : Vector.t (tape Σ) 1).
imports: Undecidability.TM.Compound.TMTac Undecidability.TM.Basic.Mono Undecidability.TM.Compound.Multi Undecidability.TM.Combinators.Combinators Undecidability.TM.Compound.WriteString