End PredicativeNotationRecursion.
Definition f_smash' :=
f 2 (proj 1 1 1)
(comp 1 3 (succ false) nil [proj 1 3 2])
(comp 1 3 (succ false) nil [proj 1 3 2]).

Lemma f_smash_inf : arities f_smash' = ok_arities 1 2.
Opaque f_smash'.