proposition: Lemma length_iP : length iP = length P.
proof: Proof. by rewrite /iP combine_length seq_length Nat.min_id. Qed.
imports: Relation_Operators Operators_Properties Lia PeanoNat List Undecidability.StackMachines.Reductions.CM1_HALT_to_SMNdl_UB.SMX_facts Undecidability.StackMachines.Util(Nat_facts List_facts) ssreflect ssrbool ssrfun