# [Tutor] [Edu-sig] collection of ACM programming problems (fwd)

**Remco Gerlich
**
scarblac@pino.selwerd.nl

*Thu, 11 Jan 2001 12:45:47 +0100*

On Thu, Jan 11, 2001 at 11:35:33AM +0000, Lindsay Davies wrote:
>* On 11/1/01, Remco Gerlich wrote about 'Re: [Tutor] [Edu-sig]
*>* collection of ACM programming pro':
*>* >On Thu, Jan 11, 2001 at 10:26:28AM +0100, Remco Gerlich wrote:
*>* >> Coolness! And we'll put our results on the Useless Python pages, yes? :)
*>* >>
*>* >> This one looks pretty simple, going to hack right away :-)
*>* >
*>* >Well, the first solution I thought of (changing the primes.py program)
*>* >didn't work out, but it was still not that hard. Fun to do though :).
*>* >Keeping the source secret for the home solvers, but the answer I get is
*>* >859963392L.
*>*
*>* OK, I could have got this completely wrong, but that seems -waaaay-
*>* too big. I get 2385.
*
But 2385/53 = 45, and 53 is a prime number. So that's not even an ugly
number itself.
Ugly numbers are the numbers that have 2, 3 and 5 as their *only* prime
factors. Numbers of the form 2^x*3^y*5^z.
Made the same mistake myself at first :)
Hmm. Math. Maybe this belongs over on python-list...
--
Remco Gerlich