Section fractran_mma.
Variables (ll : list (nat*nat)) (Hll : Forall (fun c => fst c <> 0 /\ snd c <> 0) ll).
Let i := 1.
Definition fractran_mma := mma_fractran_step i ll i.

Theorem fractran_mma_reduction x :
ll /F/ x ↓ <-> (i,fractran_mma) /MM2/ (i,x##0##vec_nil) ↓.