MAYBE
50.52/21.31	MAYBE
50.52/21.31	
50.52/21.31	Problem:
50.52/21.31	 a(x1) -> x1
50.52/21.31	 a(x1) -> b(c(x1))
50.52/21.31	 a(b(b(x1))) -> b(b(a(a(x1))))
50.52/21.31	
50.52/21.31	Proof:
50.52/21.31	 Open
50.52/21.31	EOF