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2010-09-02, 13:37   #12
alpertron

Aug 2002
Buenos Aires, Argentina

31×43 Posts

Quote:
 Originally Posted by R.D. Silverman Check Brent's tables!!!!
Notice that my ECM applet already checks for factors included in Brent's tables, which is old: updated 11 September 2009 according to his Web site.

 2010-09-03, 10:20 #13 fivemack (loop (#_fork))     Feb 2006 Cambridge, England 2·29·109 Posts 115^128+1 completed (250 curves at 1e7 were enough); result in factordb.com 101^128+1 also completed So: 400 curves at 1e7 on the not-previously-fully-factored numbers in {94..115}^128+1. This took one night on 16 threads on a macpro. 35^128+1 currently finishing linalg Last fiddled with by fivemack on 2010-09-04 at 07:50
 2010-09-03, 21:15 #14 fivemack (loop (#_fork))     Feb 2006 Cambridge, England 2·29·109 Posts 35^128+1 = 2 * 769 * 77310721 * 465774259823008864434412748488285224928909076514051885029488061896961 * P118
2010-09-03, 21:25   #15
ET_
Banned

"Luigi"
Aug 2002
Team Italia

25×149 Posts

Quote:
 Originally Posted by fivemack 35^128+1 = 2 * 769 * 77310721 * 465774259823008864434412748488285224928909076514051885029488061896961 * P118
69 digits by ECM?!?

Luigi

2010-09-03, 21:48   #16
mdettweiler
A Sunny Moo

Aug 2007
USA (GMT-5)

792 Posts

Quote:
 Originally Posted by ET_ 69 digits by ECM?!? Luigi
It looks like this was either SNFS or GNFS (probably SNFS):
Quote:
 Originally Posted by fivemack 35^128+1 currently finishing linalg

2010-09-04, 04:24   #17
Andi47

Oct 2004
Austria

7×353 Posts

Quote:
 Originally Posted by mdettweiler It looks like this was either SNFS or GNFS (probably SNFS):
SNFS-197 with a quintic? Or did I miss something?

 2010-09-04, 07:49 #18 fivemack (loop (#_fork))     Feb 2006 Cambridge, England 2·29·109 Posts yes; x^5+35^2, x=35^26; alim=rlim=15M, Q=7.5M-17.5M, 28-bit large primes. 494 CPU-hours sieving on 8x K10+3x core2, 48 CPU-hours on 4xphenom to do the matrix step. A trivial exercise.
2010-09-04, 08:21   #19
ET_
Banned

"Luigi"
Aug 2002
Team Italia

476810 Posts

Quote:
 Originally Posted by fivemack 35^128+1 currently finishing linalg

 2010-09-13, 05:36 #20 geoff     Mar 2003 New Zealand 13·89 Posts I found this p44 factor after about 500 curves with B1=11e6: 14571454116637488440882751359138387691414529 | 8^(2^8) + 5^(2^8) If anyone wanted to finish some of these off with GNFS, I think the two smallest remaining composites (with bases <= 12) are now: 11^(2^8) + 3^(2^8) = 2 . 3430486387626057217 . 1826300595737909153428993580626433 . 132980092956629419115138154564331009 . 11765487608073254883107740674172674049 . C143 8^(2^8) + 5^(2^8) = 206102775026177 . 25083346678208656976952833 . 14571454116637488440882751359138387691414529 . C149
2010-09-13, 05:46   #21
R. Gerbicz

"Robert Gerbicz"
Oct 2005
Hungary

141110 Posts

Quote:
 Originally Posted by geoff I found this p44 factor after about 500 curves with B1=11e6: 14571454116637488440882751359138387691414529 | 8^(2^8) + 5^(2^8) If anyone wanted to finish some of these off with GNFS, I think the two smallest remaining composites (with bases <= 12) are now: 11^(2^8) + 3^(2^8) = 2 . 3430486387626057217 . 1826300595737909153428993580626433 . 132980092956629419115138154564331009 . 11765487608073254883107740674172674049 . C143 8^(2^8) + 5^(2^8) = 206102775026177 . 25083346678208656976952833 . 14571454116637488440882751359138387691414529 . C149
That p44 has been found by J. Becker on 2009-10-26, see: http://www.leyland.vispa.com/numth/f...nbn/UPDATE.txt

2010-09-13, 06:21   #22
geoff

Mar 2003
New Zealand

22058 Posts

Quote:
 Originally Posted by R. Gerbicz That p44 has been found by J. Becker on 2009-10-26, see: http://www.leyland.vispa.com/numth/f...nbn/UPDATE.txt
Thanks, I didn't know about that project. So it looks like two projects have been working independently on some of these numbers :-(

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