201.43/50.42	MAYBE
201.43/50.42	
201.43/50.42	Problem:
201.43/50.42	 a(x1) -> x1
201.43/50.42	 a(a(b(x1))) -> c(a(a(a(x1))))
201.43/50.42	 c(a(x1)) -> b(b(x1))
201.43/50.42	
201.43/50.42	Proof:
201.43/50.42	 Open
201.43/50.43	EOF