@@ -0,0 +1,16 @@
+(defun my-reduce (x y)
+ (if (= 0 (mod x y))
+ (my-reduce (/ x y) y)
+ x))
+
+(defun max-factor-impl (x cur)
+ (let ((next-x (my-reduce x cur)))
+ (if (= 1 next-x)
+ cur
+ (max-factor-impl next-x (+ 1 cur)))))
+(defun max-factor (x)
+ (max-factor-impl x 2))
+(format t "~&~S~%" (max-factor 600851475143))
