fact: Definition Γ v w P := (encode_pair (var 1) (var 1)) :: (arr (encode_pair (encode_word v) (encode_word w)) a_b_a) :: map (fun '(v, w) => arr (encode_pair (append_word (var 2) v) (append_word (var 3) w)) (encode_pair (var 2) (var 3))) ((v, w) :: P).
imports: List Lia ssreflect ssrbool ssrfun Undecidability.HilbertCalculi.HSC Undecidability.HilbertCalculi.Util.HSCFacts Undecidability.PCP.PCP