mersenneforum.org Trial-factoring efficiency
 Register FAQ Search Today's Posts Mark Forums Read

 2003-06-06, 14:35 #1 ThomRuley     May 2003 24810 Posts Trial-factoring efficiency I have a question for those of you who have more experience with factoring ranges. I was wondering what percentage of exponents I can expect to eliminate by trial-factoring to 60 bits. And for those of you who are factoring past 60 bits, what percentage does each extra bit eliminate?
 2003-06-06, 14:41 #2 Axel Fox     May 2003 1408 Posts Well, I don't have a lot of experience yet, but I know it depends strongly on how far the range has already been factored. In my range, it was factored to 58 bits and I'm factoring to 60 bits and I get about 90 factors found per range of 100.000 (from 30.000.000 to 30.100.000 for example). Axel Fox.
 2003-06-06, 15:17 #3 eepiccolo     Dec 2002 Frederick County, MD 2·5·37 Posts You can find out a lot of information about trial factoring here: http://www.mersenne.org/math.htm.
 2003-06-06, 19:33 #4 garo     Aug 2002 Termonfeckin, IE 22×691 Posts A simple rule is that factoring for n bits removes 1/n factors. So if you factor from 58 to 60 bits (2 bits only) you will find a factor every 2/60 = 1/30 exponents.
 2003-06-07, 04:40 #5 cheesehead     "Richard B. Woods" Aug 2002 Wisconsin USA 22×3×641 Posts For a thorough earlier discussion, see the thread "Does the LL test:s factorization save or waste CPU time?" in The Software forum at http://www.mersenneforum.org/viewtopic.php?t=78, especially svempasnake's table comparing the 1/n prediction to the actual number of factors found, on page 3 at Mon Sep 16, 2002 9:32 pm (http://www.mersenneforum.org/viewtop...highlight=#895).

 Similar Threads Thread Thread Starter Forum Replies Last Post garo GPU Computing 100 2019-04-22 10:58 S485122 PrimeNet 1 2007-09-06 00:52 JFB Software 23 2004-08-22 05:37 michael Software 23 2004-01-06 08:54 gbvalor Math 4 2003-05-22 02:04

All times are UTC. The time now is 00:57.

Sun May 16 00:57:29 UTC 2021 up 37 days, 19:38, 0 users, load averages: 1.62, 1.66, 1.67