Definition App : term := .\"s","t"; .\"v","a","l"; "a" "s" "t".
Definition Lam : term := .\"s";     .\"v","a","l"; "l" "s".

Lemma Lam_correct s : Lam (tenc s) ≡ tenc (lambda s).
Definition N := rho ( .\"N", "n"; "n"
!(tenc Zero)
(.\"n"; !Lam (!Lam (!App !(tenc 0) ("N" "n"))))).