MAYBE
41.69/11.80	MAYBE
41.69/11.80	
41.69/11.80	Problem:
41.69/11.80	 a(x1) -> x1
41.69/11.80	 a(x1) -> b(c(b(x1)))
41.69/11.80	 a(b(b(x1))) -> b(b(a(a(x1))))
41.69/11.80	
41.69/11.80	Proof:
41.69/11.80	 Open
41.69/11.80	EOF