MAYBE
45.12/13.25	MAYBE
45.12/13.25	
45.12/13.25	Problem:
45.12/13.25	 a(x1) -> x1
45.12/13.25	 a(b(b(x1))) -> b(b(a(b(c(x1)))))
45.12/13.25	 b(c(x1)) -> a(x1)
45.12/13.25	
45.12/13.25	Proof:
45.12/13.25	 Open
45.12/13.25	EOF