MAYBE
42.59/12.75	MAYBE
42.59/12.75	
42.59/12.75	Problem:
42.59/12.75	 a(x1) -> x1
42.59/12.75	 a(b(b(x1))) -> b(b(b(a(c(x1)))))
42.59/12.75	 c(b(x1)) -> a(x1)
42.59/12.75	
42.59/12.75	Proof:
42.59/12.75	 Open
42.59/12.76	EOF