mersenneforum.org Unknown result P1-factoring with v25.7
 Register FAQ Search Today's Posts Mark Forums Read

 2008-11-02, 18:02 #1 Joh14vers6   Nov 2008 210 Posts Unknown result P1-factoring with v25.7 After changing from v25.6 to v25.7 I got results like this with P1-factoring: [Sun Nov 02 16:38:55 2008] 24737*2^16045687+1 completed P-1, B1=130000, B2=2200000, E=6, Wd1: 9F17E134 With v25.6 I got: [Tue Oct 07 21:15:49 2008] 67607*2^15850467+1 completed P-1, B1=130000, B2=2200000, Wd1: 9A1AE89E What means E=6?
 2008-11-02, 20:13 #2 Prime95 P90 years forever!     Aug 2002 Yeehaw, FL 1E5F16 Posts It refers to Suyama's (sp?) extension to P-1 stage 2 factoring. If enough memory is available, prime95 can choose an E value greater than 2 which gives it a slightly better chance of finding a factor in stage 2 (by finding some factors above the B2 value). In short, don't worry about it
 2008-11-02, 21:10 #3 Joh14vers6   Nov 2008 28 Posts Ok thanks for the explanation. I putted some extra RAM in to speed up Stage 2 as well. That explains a lot.
 2008-11-04, 06:21 #4 markr     "Mark" Feb 2003 Sydney 3×191 Posts Aha! That explains this recent result of mine: Code: P-1 found a factor in stage #2, B1=1000000, B2=40000000. UID: markr/mr7, M820643 has a factor: 279780507749146102291903 If the exponent is p, and that factor is 2kp+1, then k is 170464201698635157, which factorises as 170464201698635157 = 3 x 5413 x 70297 x 149326579 Not that I check every one, but I hadn't seen a factor found by P-1 with one of k's factors > B2 before, so I was puzzled - until now. Thanks! Mark

 Similar Threads Thread Thread Starter Forum Replies Last Post glebm Information & Answers 4 2015-07-28 23:30 fidelitas Information & Answers 4 2014-08-20 18:36 GuyMacon PrimeNet 6 2011-05-07 03:20 ixfd64 Software 3 2010-01-08 20:41 S485122 PrimeNet 0 2009-03-10 07:01

All times are UTC. The time now is 12:08.

Wed Jan 26 12:08:54 UTC 2022 up 187 days, 6:37, 0 users, load averages: 1.25, 1.23, 1.26