From Undecidability.MinskyMachines
From Undecidability.FRACTRAN
(** ** HaltTM_1 reduces to FRACTRAN_HALTING  *)

(* Many-one reduction from Turing machine halting to FRACTRAN (regular) halting *)
Lemma HaltTM_to_FRACTRAN_REG_HALTING : HaltTM 1 ⪯ FRACTRAN_REG_HALTING.