Last Friday's puzzle
Vadim asked the following brain teaser:
How many squares are there on a chess board?
Yes, it's a trick question but the solutions were better than the question or the answer.
Ik came up with a solution in Emacs Lisp:
<code>(let ((f (lambda (n) (cond ((= n 1) 1) (t (+ (* n n) (f (1- n)))))))) (f 8))</code>
Bill came up with one using DC, the RPN desk calculator, that just floored us and had us running to read the man pages: