MAYBE
143.18/55.76	MAYBE
143.18/55.76	
143.18/55.76	Problem:
143.18/55.76	 a(c(a(x1))) -> c(a(c(x1)))
143.18/55.76	 a(a(b(x1))) -> a(d(b(x1)))
143.18/55.76	 a(b(x1)) -> b(a(a(x1)))
143.18/55.76	 d(d(x1)) -> a(d(b(x1)))
143.18/55.76	 b(b(x1)) -> b(c(x1))
143.18/55.76	 a(d(c(x1))) -> c(a(x1))
143.18/55.76	 b(c(x1)) -> a(a(a(x1)))
143.18/55.76	
143.18/55.76	Proof:
143.18/55.76	 Open
143.18/55.76	EOF