20110223, 10:51  #1 
Sep 2008
Krefeld, Germany
11100110_{2} Posts 
need some advice: gnfs C164 from 162126:i4274
I think about gnfs'ing this one.
GMPECM failed to find a factor, did 2k curves at B1=110M, B2=default. Enough I guess? This poly came up quite early: Code:
# norm 6.257845e16 alpha 6.143336 e 8.508e13 rroots 3 skew: 20836454.90 c0: 15679837385732869622529327137425328966325 c1: 634300527717663660453424437257893 c2: 171419531873315925748960917 c3: 11750273807052233661 c4: 729125354572 c5: 12036 Y0: 74454053249923833901454562105026 Y1: 442492487829916909 I would have chosen: rlim: 30M alim: 30M lpbr: 31 lpba: 31 mfbr: 62 mfba: 62 rlambda: 2.7 alambda: 2.7 and the 15esiever, sieving from 15M up, algebraic side only. Any comments/advice on this one? 
20110223, 12:44  #3 
Sep 2008
Krefeld, Germany
2·5·23 Posts 
If anyone is interested in participating  sure, lets make it another team sieve! I can also do the postprocessing afterwards.

20110223, 14:10  #4 
Oct 2006
vomit_frame_pointer
2^{2}×89 Posts 
Do more ECM. 2000 curves at 11e7 is nowhere near enough.
I'd do another 6000 before sieving. Last fiddled with by FactorEyes on 20110223 at 14:23 
20110223, 15:01  #5 
Sep 2008
Krefeld, Germany
2·5·23 Posts 

20110224, 07:40  #6 
Sep 2009
977_{10} Posts 
Judging by previous team sievings for Aliquot 4788, a 31bit LPs task with 15e might be slightly aggressive for a C164 GNFS. AFAICT, 30bit LPs task with 15e, or a 31bit LPs task with 14e, would be more in line with previous sievings.
But yeah, for now, this number needs more ECM, until at least t50. 
20110314, 13:58  #7 
Sep 2008
Krefeld, Germany
2·5·23 Posts 
I just finished this one using 14e and 31bit LP, needed 160M relations to build a 9,3Mmatrix. Almost a nice split! Maybe rlim/alim was a little too low, but still quite fast.
prp81 factor: 581961354791396552117021757640957983720026694275473538439704344834014177515059043 prp83 factor: 47318351303826266855330899870715547902208735682285930149249021834006959676298350389 Last fiddled with by Syd on 20110314 at 14:50 Reason: typo 
20110314, 18:35  #8  
"Frank <^>"
Dec 2004
CDP Janesville
4062_{8} Posts 
Quote:


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