Date: Thu, 01 Nov 2007 11:56:27 GMT
> It's ironic you should mention base 9. It's a little-known fact that, if
> a number is evenly divisible by 8, the sum of the digits of the number
> in base 9 is also evenly divisible by 8. And if one repeats the process
> with that sum until the resulting sum has only one digit and if the
> original number was divisible by 8, the one remaining digit will be 8.
> It's like magic. So it's really ironic you should mention base 9 in
This is a joke, right? For radix n, n-1 has this interesting property. Likewise, 9 has this fun property in decimals. Bookkeepers in the Bob Chratchit era used a property much like this one for error detection in manually managed numbers.
If this were another person posting, I'd think it was simple oversight. But you, BB, are likely to know exactly what I've just said. Received on Thu Nov 01 2007 - 12:56:27 CET