199.24/50.17	MAYBE
199.24/50.17	
199.24/50.17	Problem:
199.24/50.17	 a(a(a(x1))) -> b(x1)
199.24/50.17	 a(b(b(x1))) -> b(a(a(b(a(x1)))))
199.24/50.17	
199.24/50.17	Proof:
199.24/50.17	 Open
199.24/50.18	EOF