MAYBE
27.16/10.18	MAYBE
27.16/10.18	
27.16/10.18	Problem:
27.16/10.18	 a(x1) -> b(c(x1))
27.16/10.18	 b(a(b(x1))) -> x1
27.16/10.18	 c(c(x1)) -> a(a(a(b(x1))))
27.16/10.18	
27.16/10.18	Proof:
27.16/10.18	 Open
27.16/10.18	EOF