MAYBE
28.66/10.19	MAYBE
28.66/10.19	
28.66/10.19	Problem:
28.66/10.19	 a(x1) -> x1
28.66/10.19	 a(a(a(x1))) -> b(x1)
28.66/10.19	 b(c(x1)) -> c(c(a(b(x1))))
28.66/10.19	 c(x1) -> x1
28.66/10.19	
28.66/10.19	Proof:
28.66/10.19	 Open
28.66/10.19	EOF