View Full Version : P-1 factoring for SOB sieve

07-06-2007, 12:40 PM
P-1 factoring is in need of mores cores to stay ahead of PRP. I was asked to recruite some team members. So I am posting this and I think it may be a better way to get some SOB Sieve points. The results for P-1 factoring are turned into SOB Sieve. After running SOB Sieve for over a month I learned there was P-1 factoring that may earn us points sooner for SOB Sieve.

I just found a factor for P-1 that should turn into 1.3 million points in about a month. Some of my factors found by Sieveing could take several months to years to turn into major points. Most of them right now are worth only 12 points.

P-1 factoring uses Prime95 with a special ini. Info can be found in thread:


At the end of the following thread it talks about the need for more P-1 factoring:


The following thread is where I asked about how to get more points and was directed to the P-1 stuff:


07-06-2007, 10:11 PM
How about a How_To procedure summary for spooners* (like me)?

I assume step #1 is: register a forum account at free-dc.org.

*meaning "spoon fed" as in net lingo "newbie"

07-07-2007, 08:35 AM
Step 1: Get an account for the following forum:

Step 2: In the above forum reserve a small range to start with. The last range I reserved was 14013000 14017000. That may take me about 3 weeks to complete on a Q6400 running at 3.0 Gig.

Step 3: The following link has a "how to list". Ignore the part about how to create a worktodo.ini file for PRIME95. For getting the worktodo.ini file go to the 2nd entry in the thread http://www.free-dc.org/forum/showthread.php?t=3239 . You will see some worktodo.ini zip files. Pick the one that has your range. Edit this file to only include your range to work on. An example of a portion of my worktodo.ini is:


A couple of things in the instruction in the above link is to:

Move the worktodo.ini to folder where PRIME95 is.

Add the following line to the prime.ini file.


Step 4: After you start PRIME95 go to its options for the CPU. Set the amount of memory to use. I have mine at 600 meg. When I 1st ran this I was using the default of 8 meg and when my PRIME95 got up to doing Stage 2 it said it did not have enough memory.

Step 5: Factors that are found get submited to: http://www.seventeenorbust.com/sieve/ . Before summiting a factor you have to edit it to be in the following format:

1232968284089849 | 258317*2^17969351+1

Step 6: When range is comple go to thread where reserved range and say it is complete.

Step 7: Here is a link to the stats page http://www.henleyclan.co.uk/sobsieve/alltime/scores.htm . Here is a link to my stats http://www.henleyclan.co.uk/sobsieve/alltime/ui/13090.htm . In it there is a line like:

Factors next to enter (main) 'active window' (@n=13842150)

The number 13842150 will be increasing as time goes on and is the number where our P-1 factoring should be kept ahead of. The one factor that I have found with P-1 factoring in my stats is:

2126.847T 55459 14001286

In about a few weeks the active window will be up to 14001286 and the points for my factor will be increased.

[XC] riptide
07-07-2007, 03:08 PM
Good man Glennpat. :)

Joe O
07-10-2007, 04:04 PM
So where is the influx of factorers?

[XC] riptide
07-10-2007, 04:13 PM
Welcome Joe O! For those who may (or may not know) Joe O is a moderator on the Free-DC hosted Seventeen or Bust forums.....

or I'm going slightly mad. :)

Joe O
07-10-2007, 06:08 PM
riptide;2301230']Welcome Joe O! For those who may (or may not know) Joe O is a moderator on the Free-DC hosted Seventeen or Bust forums.....

or I'm going slightly mad. :)

Thanks for the welcome.
I'm not going to comment on the second possibility <G>, but I am that Joe O.
I thought that I would try to stir some interest here in P-1 factoring. Glennpat seems to be enjoying himself. We could use a few more people like him.

Joe O
08-02-2007, 06:47 PM
Well the first of Glennpat's P-1 factors are beginning to score big:

Largest scores
p (T) k n Score Factor found Score changed Score was Score could be Reqd bias PRP saved
9555.392T 10223 14003801 837447.845 Sat 14-Jul-2007 Thu 02-Aug-2007 35.000 5855856.108 238.88 (2) glennpat
2126.847T 55459 14001286 837147.071 Fri 06-Jul-2007 Thu 02-Aug-2007 21.268 1302933.098 53.17 (2) glennpat

[XC] 4X4N
08-02-2007, 07:25 PM
Kick ass Glenn :up:

08-03-2007, 12:39 PM
Thanks for the notice. I'm doing a little more kicking today. I got another 2.5 million points today and we're passing 3 teams. All the crunching is finally generating some real points. I have a couple of more factors that will be upgraded soon. Most of the rest are long ways off.

I am still doing some p-1 so should get some more close factors, but the last range I have been running for 10 days has not turning up one yet.

08-05-2007, 01:13 PM
I just found a factor using P-1 today. That was kind of a long run without finding one and it sure was nice to see it there. Hopefully there will be a few close together now.

08-05-2007, 05:12 PM
Are those .ini's 1-to-1 compatible with Linux mprime or should Linux users use Wine (to emulate Win32)?

Joe O
08-06-2007, 08:20 AM
Are those .ini's 1-to-1 compatible with Linux mprime or should Linux users use Wine (to emulate Win32)?

Good question! I was wondering about Mprime myself. Why don't you try it and let us know. It would also be interesting to see a speed comparison against Pime95 running under Wine. Again let us know if you try it and what the results are.

Joe O
10-31-2007, 10:12 AM
The worktodo.ini.zip files have been updated with the removal of k=33661 and the processing of all submitted factors.