;; IVY operation: PROVE
;;
;; Theorem CN19 from the McCune/Wos Condensed Detachment paper (CADE-11).

(imp (and (all x (all y (imp (and (p (i x y)) (p x)) (p y))))
	  (all x (all y (all z (P (i (i x y) (i (i y z) (i x z)))))))
	  (all x (P (i (i (n x) x) x)))
	  (all x (all y (P (i x (i (n x) y))))))

     (all a (all b (all c (P (i (i (i a b) c) (i b c)))))))
