20030605, 16:10  #12 
"Phil"
Sep 2002
Tracktown, U.S.A.
2^{5}·5·7 Posts 
It is extremely unlikely, but not impossible, that you would ever find two factors at once, but you could easily do a primality test to see if your factor is prime or not. In most cases, the size of your factor would be an important clue. Suppose you were running curves with B1=250,000 on Fermat numbers and found a factor of 30 digits or so. For this factor to be composite, it would have to have a prime factor of <= 15 digits that would have already been discovered. On the other hand, suppose you turned up a factor of 60 or so digits. The chance of two 30 digit factors showing up on the same curve is about 1 in 700^2, or 1 in 490,000, not very great. On the other hand, the chance of a 60 digit factor showing up with B1=250,000 is much, much smaller than this, so the suspicion that you had found two factors at once would probably turn out to be true.

20030618, 14:25  #13 
Jun 2003
The Computer
401 Posts 
Here's a link to ADingOD FreeRAM.
It speeds up GIMPS about 25%. You should just keep hitting "Optimize" until the numbers don't change anymore. http://www.padring.com/go.php?http://ading.hypermart.net/freeram.zip 
20030619, 00:25  #14 
Aug 2002
Dawn of the Dead
5×47 Posts 
philmoore
We have had members who found doubles in P1. The client tends to concatenate the results and the result then has too many bits for the cleared exponents page. George then intervenes.

20030704, 18:57  #15  
Jun 2003
1169_{10} Posts 
Re: philmoore
Quote:
As you have observed, the cleared exponents page does not show large factors correctly. The last composite I turned in was only shown to 100 bits, however a 102 bit prime factor was shown correctly. I don't know what the limit is. Regards Daran 

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