; @author Raul Gutierrez
; @author Salvador Lucas
; @doi 10.1007/3-540-59200-8_56
; @cops 928
; [68] Example 3.3
(format CTRS oriented :problem infeasibility)
(fun a 0)
(fun b 0)
(fun c 0)
(fun f 1)
(rule a b)
(rule (f x) c (= x a))
(infeasible? (= (f b) x) (= c x))