I just came up with this while teaching my son about numbers. Let's see how quickly somebody figures this out.
If you had a 64 bit number written down in hex, how could you quickly tell without the aid of any computational device, including pencil or paper if it is divisible by 15? How about 17? -- Sasha Pachev AskSasha Linux Consulting http://asksasha.com Fast Running Blog. http://fastrunningblog.com Run. Blog. Improve. Repeat. /* PLUG: http://plug.org, #utah on irc.freenode.net Unsubscribe: http://plug.org/mailman/options/plug Don't fear the penguin. */
