20060621, 23:13  #1 
"Jason Goatcher"
Mar 2005
DB3_{16} Posts 
Don't know how to work on Cunningham numbers.
I compiled ecm a couple weeks ago, so I know it's recent. Basically, I'd like to spend some time on one of my dualcore processor cores doing Cunningham numbers, but I have some questions:
How does the listing format work? If I remember correctly, there are 3 numbers with commas between them. How do I "translate" this into the formula? Also, and I'm sorry if actually doing the work answers the questions, but I've only done ECMNet and don't know how to do manual work. I looked through the thread titles and nothing jumped out at me as possibly being helpful. If someone wants to assign me 12 weeks of "their" work to work on my computer, I'd be glad to help. Because of some other DC work I'm doing, I'm not actually going to work on this part until Friday or Saturday, but I'm willing to experiment until then to make sure I understand how things work. Thanks for any help. :) 
20060622, 01:09  #2 
Aug 2005
Brazil
2×181 Posts 
Cunningham numbers are just 2 with a comma between them. The minus sign is normally put in.
a, b = Sometimes you'll find a plus sign, like so: a, b+ = If you're talking about homogeneous cunninghams, the formula is: a, b, n = Last fiddled with by fetofs on 20060622 at 01:10 
20060622, 10:06  #3  
"Jason Goatcher"
Mar 2005
3·7·167 Posts 
Quote:
(1) What's the best way to reserve?(Should I go to another site to reserve?) (2) Unfortunately, my room's been rearranged since I did this last, so I need instructions on making the ecm parameters. Edit: Perhaps instead I should be looking at ecm servers.(I just rediscovered the Cunningham server. Sorry for bugging you guys. :( ) Last fiddled with by jasong on 20060622 at 10:29 

20060622, 14:39  #4 
"William"
May 2003
Near Grandkid
2373_{10} Posts 
Are you aware of the Cunningham tables here on MersenneForum at
http://www.mersenneforum.org/forumdisplay.php?f=51 From here you can see that 3^{523}1 has a 233 digit composite that has had some work done at B1=110M. You can copy the decimal digits to a file and the start ecm from a command prompt as ecm 110000000 < file.txt >> results.txt 
20060623, 01:08  #5  
"Jason Goatcher"
Mar 2005
3×7×167 Posts 
Quote:
Thanks for pointing out the forum to me, though :) 

20060627, 13:50  #6  
"Bob Silverman"
Nov 2003
North of Boston
7508_{10} Posts 
Quote:
Note: Some of those tables are quite a bit out of date. A lot of numbers have been finished since the tables were last modified. Sam Wagstaff's web site contains more recent info. 

20060630, 08:51  #7 
"Nancy"
Aug 2002
Alexandria
2,467 Posts 
I've removed those numbers from our tables that are not in Sam's composites list (as of June 2006) anymore. Some remaining composites may have gotten smaller, though.
Alex 
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