689.60/299.38	MAYBE
689.60/299.38	
689.60/299.38	Problem:
689.60/299.38	 strict:
689.60/299.38	  f(0(),y) -> 0()
689.60/299.38	  f(s(x),y) -> f(f(x,y),y)
689.60/299.38	 weak:
689.60/299.38	  rand(x) -> x
689.60/299.38	  rand(x) -> rand(s(x))
689.60/299.38	
689.60/299.38	Proof:
689.60/299.38	 Open
689.60/299.38	EOF