fact: Fixpoint half (n: nat) : (nat * bool) := match n with | 0 => (0, true) | S n' => match half n' with | (m, b) => if b then (m, false) else (S m, true) end end.
imports: Undecidability(MinskyMachines.MM MinskyMachines.MMA) Undecidability.Shared.Libs.DLW(Vec.pos Vec.vec Code.sss) PeanoNat List Lia Wf_nat ssreflect ssrbool ssrfun