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From: Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups: comp.programming
Subject: Re: really? (lame question about primes)
Date: Wed, 02 Sep 2015 16:49:48 +0100
Organization: A noiseless patient Spider
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Richard Heathfield <rjh@cpax.org.uk> writes:

> On 02/09/2015 13:42, James Dow Allen wrote:
<snip>
>> I'll be impressed by whoever is first to factor this number
>> 6666666666666666666666666666666664295863450544367679162527001239842359
>> (Please tell us how you did it.)
>
> Ben posted his answer before I'd even read the question! It's a shame
> that his embarrassment prevents him from revealing his method, but
> perhaps it's for the best - if he explained, we would say (just as
> Watson said after Holmes had explained a deduction) "Oh, how absurdly
> simple!" So let's just applaud Ben and spare him his blushes.

It's embarrassing only because I did nothing interesting.  I ran 'gp'
and typed

 factor(6666666666666666666666666666666664295863450544367679162527001239842359)

at the prompt just to see if it could, and after minute or two it
replied:

  %1 = 
  [67499999992406250000094921874999003 1]
  [98765432109876543210987654321098453 1]

(the 1s because it shows a list of primes and powers).  It would be so
much better if I could have talked about elliptic curves and number
field sieves so as to appear wise.  Oh look, I just did!

-- 
Ben.