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2006-04-12, 17:51   #34
xilman
Bamboozled!

May 2003
Down not across

22×41×61 Posts

Quote:
 Originally Posted by R.D. Silverman It is quite possible. I have not checked them. Which factor?
When I get my act together (the Easter weekend, I hope) I'll run the same data-preening code that is used on the other tables I maintain.

Paul

 2006-04-12, 17:52 #35 Phil MjX     Sep 2004 5·37 Posts 400 (16,80) 19995617469086942401.C134 19995617469086942401=P10 * P10 P10 = 4388625601 P10 = 4556236801 with Tomabechi P-1 (including apr-cl) oops, 3 min too late !! P.S. Last fiddled with by Phil MjX on 2006-04-12 at 17:53
2006-04-12, 19:03   #36
R.D. Silverman

Nov 2003

3·2,473 Posts

Quote:
 Originally Posted by Greenbank 400 (16,80) 19995617469086942401.C134 19995617469086942401 = 4388625601 x 4556236801
It is probable that this was found by P-1 and that the factor
was not checked for primality...... mea culpa.

2006-04-12, 19:36   #37
Andi47

Oct 2004
Austria

2×17×73 Posts

Quote:
 Originally Posted by Andreas Schinde Done 648 curves on 3^379+2^379 using GMP-ECM at B1=1e6 and B2=default, no factor found. Together with Silverman's ~300 curves this should have finished the 35 digit range. Now running a some curves with B1=3e6 at this number.
Done 300 curves with B1=3e6, no factor found.

2006-04-12, 23:17   #38
Greenbank

Jul 2005

38610 Posts

Quote:
 Originally Posted by R.D. Silverman It is probable that this was found by P-1 and that the factor was not checked for primality...... mea culpa.
Looks that way, those factors are both very smooth:-

4388625600 = 2^6 x 3 x 5^2 x 89 x 10273
4556236800 = 2^11 x 3 x 5^2 x 29663

 2006-04-13, 09:19 #39 Jushi     Sep 2005 UGent 22·3·5 Posts Some ECM work: Some ECM work (format: [#curves]@[B1 bound], other parameters are the ecm default) 3,2,343- (C136) 650@1e6, 40@3e6 3,2,371- (C141) 2440@3e6 3,2,391- (C161) 345@1e6
 2006-04-13, 12:35 #40 Yamato     Sep 2005 Berlin 2·3·11 Posts For those who are interested: Look at http://www.cip.mathematik.uni-stuttg...nt/ex3k2k.html
2006-04-13, 12:44   #41
R.D. Silverman

Nov 2003

3×2,473 Posts

Quote:
 Originally Posted by Yamato For those who are interested: Look at http://www.cip.mathematik.uni-stuttg...nt/ex3k2k.html

You have some composites in your results that I have already finished.
I have finished everything for 3^n +/- 2^n up to n = 336 (3^335 - 2^335)
was just finished here a day or two ago by someone else.

I could easily finish everything to n = 400, but I am busy with other
things...

 2006-04-13, 15:44 #42 akruppa     "Nancy" Aug 2002 Alexandria 2,467 Posts This thread fits better into Factoring than GMP-ECM. Moved. Alex
 2006-04-13, 15:49 #43 Pascal Ochem     Apr 2006 89 Posts The factors of the C111 from 3^372+2^372 are: 840497702349180597209469882198293789055301120886641 (pp51) 766974650561302741840583863816378225180158232426458907919137 (pp60) with ggnfs (pp=probable prime)
2006-04-13, 16:00   #44
R.D. Silverman

Nov 2003

1CFB16 Posts

Quote:
 Originally Posted by Pascal Ochem The factors of the C111 from 3^372+2^372 are: 840497702349180597209469882198293789055301120886641 (pp51) 766974650561302741840583863816378225180158232426458907919137 (pp60) with ggnfs (pp=probable prime)
Nice. I am a bit surprised however. I didn't think enough ECM
effort had been expended to proceed with NFS on these numbers.

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