MAYBE
42.94/13.00	MAYBE
42.94/13.00	
42.94/13.00	Problem:
42.94/13.00	 a(x1) -> x1
42.94/13.00	 a(a(b(x1))) -> b(b(a(a(x1))))
42.94/13.00	 b(x1) -> a(c(a(x1)))
42.94/13.00	
42.94/13.00	Proof:
42.94/13.00	 Open
42.94/13.00	EOF