diff --git a/17.rkt b/17.rkt
index d2f2a19..164e16f 100644
--- a/17.rkt
+++ b/17.rkt
@@ -6,6 +6,7 @@
 
 (struct pt [x y z w] #:transparent)
 (define pt-getters (list pt-x pt-y pt-z pt-w))
+(define origin (pt 0 0 0 0))
 
 (define (pt+ . args)
   (for/fold ([ans (pt 0 0 0 0)]) ([x (in-list args)])
@@ -21,13 +22,7 @@
     (pt x y z w)))
 
 (define nearby/4d
-  (for*/list ([x (in-range -1 2)]
-              [y (in-range -1 2)]
-              [z (in-range -1 2)]
-              [w (in-range -1 2)]
-              #:unless (and (zero? x) (zero? y) (zero? z) (zero? w)))
-    (pt x y z w)))
-
+  (for/list ([pt (in-pts origin origin #t)] #:unless (equal? pt origin)) pt))
 (define nearby/3d (filter #{zero? (pt-w %)} nearby/4d))
 
 (define (calc-bounds world)