mersenneforum.org  

Go Back   mersenneforum.org > Factoring Projects > Factoring

Reply
 
Thread Tools
Old 2006-04-12, 17:51   #34
xilman
Bamboozled!
 
xilman's Avatar
 
May 2003
Down not across

100110011101012 Posts
Default

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
xilman is offline   Reply With Quote
Old 2006-04-12, 17:52   #35
Phil MjX
 
Phil MjX's Avatar
 
Sep 2004

B916 Posts
Default

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
Phil MjX is offline   Reply With Quote
Old 2006-04-12, 19:03   #36
R.D. Silverman
 
R.D. Silverman's Avatar
 
Nov 2003

3·23·107 Posts
Default

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.
R.D. Silverman is offline   Reply With Quote
Old 2006-04-12, 19:36   #37
Andi47
 
Andi47's Avatar
 
Oct 2004
Austria

2×17×73 Posts
Default

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.
Andi47 is offline   Reply With Quote
Old 2006-04-12, 23:17   #38
Greenbank
 
Greenbank's Avatar
 
Jul 2005

2·193 Posts
Default

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
Greenbank is offline   Reply With Quote
Old 2006-04-13, 09:19   #39
Jushi
 
Jushi's Avatar
 
Sep 2005
UGent

22·3·5 Posts
Default 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
Jushi is offline   Reply With Quote
Old 2006-04-13, 12:35   #40
Yamato
 
Yamato's Avatar
 
Sep 2005
Berlin

1028 Posts
Default

For those who are interested: Look at
http://www.cip.mathematik.uni-stuttg...nt/ex3k2k.html
Yamato is offline   Reply With Quote
Old 2006-04-13, 12:44   #41
R.D. Silverman
 
R.D. Silverman's Avatar
 
Nov 2003

738310 Posts
Default

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...
R.D. Silverman is offline   Reply With Quote
Old 2006-04-13, 15:44   #42
akruppa
 
akruppa's Avatar
 
"Nancy"
Aug 2002
Alexandria

2,467 Posts
Default

This thread fits better into Factoring than GMP-ECM. Moved.

Alex
akruppa is offline   Reply With Quote
Old 2006-04-13, 15:49   #43
Pascal Ochem
 
Pascal Ochem's Avatar
 
Apr 2006

23·11 Posts
Default

The factors of the C111 from 3^372+2^372 are:

840497702349180597209469882198293789055301120886641 (pp51)
766974650561302741840583863816378225180158232426458907919137 (pp60)

with ggnfs (pp=probable prime)
Pascal Ochem is offline   Reply With Quote
Old 2006-04-13, 16:00   #44
R.D. Silverman
 
R.D. Silverman's Avatar
 
Nov 2003

3×23×107 Posts
Default

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.
R.D. Silverman is offline   Reply With Quote
Reply

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
New phi for homogeneous Cunningham numbers wpolly Factoring 26 2016-07-29 04:34
Mathematics of Cunningham Numbers (3rd ed., 2002, A.M.S.) Xyzzy Cunningham Tables 42 2014-04-02 18:31
Don't know how to work on Cunningham numbers. jasong GMP-ECM 6 2006-06-30 08:51
Doing Cunningham numbers but messed up. jasong Factoring 1 2006-04-03 17:18
Need help factoring Cunningham numbers jasong Factoring 27 2006-03-21 02:47

All times are UTC. The time now is 21:53.

Sat Apr 4 21:53:13 UTC 2020 up 10 days, 19:26, 0 users, load averages: 1.70, 1.56, 1.60

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.

This forum has received and complied with 0 (zero) government requests for information.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation.
A copy of the license is included in the FAQ.