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Old 2010-09-02, 13:37   #12
alpertron
 
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Quote:
Originally Posted by R.D. Silverman View Post
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.
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Old 2010-09-03, 10:20   #13
fivemack
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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
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Old 2010-09-03, 21:15   #14
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35^128+1 = 2 * 769 * 77310721 * 465774259823008864434412748488285224928909076514051885029488061896961 * P118
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Old 2010-09-03, 21:25   #15
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Quote:
Originally Posted by fivemack View Post
35^128+1 = 2 * 769 * 77310721 * 465774259823008864434412748488285224928909076514051885029488061896961 * P118
69 digits by ECM?!?

Luigi
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Old 2010-09-03, 21:48   #16
mdettweiler
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Quote:
Originally Posted by ET_ View Post
69 digits by ECM?!?

Luigi
It looks like this was either SNFS or GNFS (probably SNFS):
Quote:
Originally Posted by fivemack View Post
35^128+1 currently finishing linalg
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Old 2010-09-04, 04:24   #17
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Quote:
Originally Posted by mdettweiler View Post
It looks like this was either SNFS or GNFS (probably SNFS):
SNFS-197 with a quintic? Or did I miss something?
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Old 2010-09-04, 07:49   #18
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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.
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Old 2010-09-04, 08:21   #19
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Quote:
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35^128+1 currently finishing linalg
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Old 2010-09-13, 05:36   #20
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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
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Old 2010-09-13, 05:46   #21
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Quote:
Originally Posted by geoff View Post
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
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Old 2010-09-13, 06:21   #22
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Quote:
Originally Posted by R. Gerbicz View Post
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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