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Old 2004-04-25, 23:56   #5
Maybeso
 
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Aug 2002
Portland, OR USA

2·137 Posts
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dsouza123,

After some experimenting, I don't think the first 5 digits will help reduce the search.

Using the first 10 digits of RSA-640, we make a real number, like this: 310741.8240
then look for pairs of smaller reals, like this:
Code:
310.75	999.97		500.00	621.48		550.00	564.98
310.76	999.94		500.01	621.47		550.01	564.97
310.77	999.90		500.02	621.45		550.02	564.96
310.78	999.87		500.03	621.44		550.03	564.95
310.79	999.84		500.04	621.43		550.04	564.94
Because each of the smaller numbers has 90 digits trailing it, we can't treat them like 5 digit integers. So given 'a', c = a/b has a solution for any b.

We can only use the first 5 digits to finish constructing a factor pair after we find them using the last 5 digits.
But you have success, because we are thinking about it!

Last fiddled with by Maybeso on 2004-04-25 at 23:57
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