20090601, 17:58  #1 
(loop (#_fork))
Feb 2006
Cambridge, England
2·7·461 Posts 
2^8771 polynomial selection
Another month, another 17xdigit GNFS.
Pick a number between zero and 1000 which hasn't been picked before, and post saying which you've picked; as far as I know, you're no more likely to find a good polynomial in any range than in any other. I will use '389' as the example number. Put the line Code:
N 2426823897740521871358050077978548270356369169858920055316001626238737543956741884688508977082673772430933692083180285944173725894314917788842645762469500115886775910459988933319 Obtain (from http://www.mersenneforum.org/showpos...10&postcount=2, or by building them yourself from ggnfs svn) the pol51m0b and pol51opt executables. Run Code:
pol51m0b b M877.389 p 8 n 1.7e26 a 38900000 A 39000000 which will take about 14 hours on one core2/2400 core (NB it's much quicker for smaller ranges, only about three hours for range 000) and produce a file M877.389.51.m with between a few hundred and a few thousand lines. Run Code:
pol51opt n 1.3e26 N 2e23 b M877.389 e 7.0e14 Code:
BEGIN POLY #skewness 302984.00 norm 7.07e+24 alpha 5.07 Murphy_E 7.08e14 X5 38902471200 X4 175620852038927313 X3 26362636095106986685408 X2 4619269142557809418631719430 X1 935036711601700177680636473088168 X0 50242391282148099865092144031788410688 Y1 7163709297211109687 Y0 2285663093636710791536341014657281 M 720342180002848932822665197147412139722267501887950287595140130145869592769744535047190636191707397163967515655793706388645419869266262883407109959170159333145235003312628195150 Code:
grep urph M877.389.cand  sort g k 10  tail Repeat the whole process until June 18th or until you're fed up. I suspect there's a polynomial with a score better than 1.1e13 to be found, and every 0.01e14 improvement in the score will save us several dozen CPUhours at the sieving stage; we'll start sieving on Midsummer's Day with the best polynomial that's been found by June 18th Reservations antiroach 05 done 8.15e14 antiroach 520 except 14 done nothing of interest axn 14 done 8.26e14 frmky 20112 except 28, 47 and 56 done nothing of interest axn 28 done 7.38e14 andi47 47 done 7.35e14 axn 56 done nowt axn 112 done nowt frmky 113200 done nothing of interest smh 200 done nowt fivemack 200224 done 9.23e14 axn 224 done 7.59e14 frmky 225300 nothing of interest frmky 300360 done 8.92e14 frmky 360380 done 8.03e14 fivemack 380400 done 8.25e14 fivemack 400500 done 9.21e14 frmky 500600 done 9.20e14 frmky 600800 fivemack 8001000 fivemack 10001200 done 8.87e14 fivemack 12001260 done 8.39e14 fivemack 12601300 Last fiddled with by fivemack on 20090613 at 17:00 Reason: add example 
20090601, 18:14  #2  
"Bob Silverman"
Nov 2003
North of Boston
2^{3}·3·313 Posts 
Quote:


20090601, 19:30  #3 
Jul 2003
So Cal
2,621 Posts 
frmky 360380

20090601, 19:37  #4 
Jun 2003
2^{2}·61 Posts 
antiroach 05
Is there a way to track progress when running pol51m0b? Last fiddled with by antiroach on 20090601 at 19:39 
20090602, 03:07  #5 
Jul 2003
So Cal
2,621 Posts 
That went much more quickly than expected. The best poly was
Code:
BEGIN POLY #skewness 882095.12 norm 7.89e+24 alpha 5.96 Murphy_E 8.03e14 X5 37551413340 X4 18912546537876037 X3 113814576528461898290387 X2 10359196566616328061415711938 X1 31062438900126333398445772457845543 X0 43103716967954269114239865122595502805 Y1 3785186493283328947 Y0 2301878492779152102060887803551802 M 16793546605175154476732525265645227867084626485392719897672431260069383174679471313393931995945360183033878$ END POLY frmky 300360 
20090602, 03:43  #6 
Jun 2003
2×7×389 Posts 
Reserving 14 and 28

20090602, 07:11  #7 
Jun 2003
2·7·389 Posts 
14 done. Reserving 56 (BTW, it is NOT 12,24)
Best is a 8.26. Second best is 7.71 Code:
BEGIN POLY #skewness 2079772.57 norm 6.16e+024 alpha 5.84 Murphy_E 8.26e014 X5 1467231360 X4 13840631600912371 X3 20518074718309616991592 X2 23127033341910364722302550846 X1 40611190451383792230615253375297342 X0 6259244685376033177460376064968265982285 Y1 1733396567827630211 Y0 4402586850256143045312923816672808 M 1127974133821908515271331948508183117127869869657001963831217889258458949658553855593125629438683729386138901328891688368946213153236864552790689946357410782499007463716679254683 END POLY 
20090602, 07:43  #8 
(loop (#_fork))
Feb 2006
Cambridge, England
2×7×461 Posts 
Yes, do 'type M877.001.51.m' (on Windows, 'cat M877.001.51.m' on Unix) and see what the first number in the last line is
Last fiddled with by fivemack on 20090602 at 07:43 
20090602, 08:06  #9 
Jun 2003
1010101000110_{2} Posts 
28 done. Nothing worth reporting, the best being a 7.38
Reserving 112. 
20090602, 10:46  #10 
Jun 2003
1010101000110_{2} Posts 
56 done. Zero polynomials :(
Reserving 224 
20090602, 12:30  #11 
Jun 2003
2×7×389 Posts 
112 done. Zero again.

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