(**************************************************************)
(*   Copyright Dominique Larchey-Wendling [*]                 *)
(*             Yannick Forster            [+]                 *)
(*                                                            *)
(*                             [*] Affiliation LORIA -- CNRS  *)
(*                             [+] Affiliation Saarland Univ. *)
(**************************************************************)
(*      This file is distributed under the terms of the       *)
(*         CeCILL v2 FREE SOFTWARE LICENSE AGREEMENT          *)
(**************************************************************)
(** ** FRACTRAN_HALTING is undecidable *)
From Undecidability.MinskyMachines
From Undecidability.FRACTRAN
Check FRACTRAN_REG_undec.

Theorem FRACTRAN_undec : undecidable FRACTRAN_HALTING.