I wrote it up here: http://noahtheduke.github.io/posts/2021-10-02-from-elegance-... I'm not a great writer, but hopefully you enjoy it!

I also found a small bug, that you'll want to use `(elt s (+ x 7))`, not `(+ x 8)`. `elt` is 0-indexed, so first and last of an 8 element list will be 0 and 7.