;; IVY operation: MODEL
;;
;; Find a model of "there is a noncommutative group".

(and (= (f (e) x) x)
     (= (f (g x) x) (e))
     (= (f (f x y) z) (f x (f y z)))

     (exists x (exists y (not (= (f x y) (f y x))))))
