MAYBE
43.77/12.17	MAYBE
43.77/12.17	
43.77/12.17	Problem:
43.77/12.17	 a(b(x1)) -> x1
43.77/12.17	 a(c(x1)) -> b(b(x1))
43.77/12.17	 c(b(x1)) -> a(a(c(c(x1))))
43.77/12.17	
43.77/12.17	Proof:
43.77/12.17	 Open
43.77/12.17	EOF