mersenneforum.org  

Go Back   mersenneforum.org > Factoring Projects > FermatSearch

Reply
 
Thread Tools
Old 2018-08-04, 19:58   #23
rogue
 
rogue's Avatar
 
"Mark"
Apr 2003
Between here and the

170E16 Posts
Default

Quote:
Originally Posted by ET_ View Post
Done

Would you mind spending 2 words explaining why adding N values helps deepen the search? Would extending the k range have the same result, or the opposite?
Adding n means at most one addition and one bit shift per n per prime. This is much faster than sieving two consecutive n separately as each n would require one powmod per prime. In this case I have replaced a powmod with an add and bit shift.

Adding k only increases the memory needed for sieving, but won't slow down the sieve once you get p > max k.
rogue is online now   Reply With Quote
Old 2018-08-13, 12:55   #24
rogue
 
rogue's Avatar
 
"Mark"
Apr 2003
Between here and the

170E16 Posts
Default

Both of these range are done. Nothing new to report beyond the Fermat divisor that I already reported.

n: 5100-5199 k:1200e6-2500e6
n: 5100-5299 k:1200e6-2500e6
rogue is online now   Reply With Quote
Old 2018-08-19, 21:54   #25
rogue
 
rogue's Avatar
 
"Mark"
Apr 2003
Between here and the

10111000011102 Posts
Default

I have to redo

n: 5000-5399 k:1200e6-2500e6

because of the bug gfndsieve had with ABCD files which I fixed with the 1.7.2 release of mtsieve in July. Although that bug only impacts starting gfndsieve from an previous save point, I suspect that the other large ranges I have sieved with it need to be re-run. n 5400-5599 are fine. There is another large gap I did a few months ago that I will re-run. I doubt any of the smaller ranges I have done are impacted, but they should be "thrown back into the pool" to be redone. Unfortunately for me this is about 6 months of rework.

If anyone used a build of gfndsieve that is prior than the 1.7.2 release of mtseive and you stopped and restarted sieving from a saved file, you will need to redo that range. If you did not stop and restart then you are fine.

Last fiddled with by rogue on 2018-08-19 at 22:03
rogue is online now   Reply With Quote
Old 2018-12-13, 16:52   #26
rogue
 
rogue's Avatar
 
"Mark"
Apr 2003
Between here and the

2×13×227 Posts
Default

I finished the recheck of n 5000-5399 and completed n 5400-5599 for k 1200e6-2500e6. Here are my finds:

2222488721*2^5349+1 is a Factor of xGF(5347,7,3)!!!!
2055442709*2^5431+1 is a Factor of GF(5429,11)!!!!
1994861771*2^5517+1 is a Factor of xGF(5512,7,2)!!!!
1321981497*2^5592+1 is a Factor of xGF(5590,7,5)!!!!

Nothing was missed in 5000-5299.

I have rested all other ranges that I had completed previously with the the exception of n: 10003-10999 k: 100e6 269e6. I expect that to complete in February. Based upon sieving, I know that range was impacted by the bug in gfndsieve.
rogue is online now   Reply With Quote
Old 2019-11-22, 10:14   #27
ET_
Banned
 
ET_'s Avatar
 
"Luigi"
Aug 2002
Team Italia

476610 Posts
Default Some new "Most wanted" ranges

Quote:
Originally Posted by ATH View Post
I admit I did some factoring without making a reservation but I did check the Reservation thread and here: http://www.fermatsearch.org/stat/running.php

I was running mmff-0.28 near the maximum range which is n<=223 and k*2n+1 <= 2252. I completed the maximum available ranges that mmff-0.28 can do:


Code:
no factor for k*2^205+1 in k range: 130000000000000 to 140737488355327 (252-bit factors) [mmff 0.28 mfaktc_barrett252_F192_223gs]

no factor for k*2^204+1 in k range: 130000000000000 to 140737488355327 (251-bit factors) [mmff 0.28 mfaktc_barrett252_F192_223gs]
no factor for k*2^204+1 in k range: 140737488355328 to 281474976710655 (252-bit factors) [mmff 0.28 mfaktc_barrett252_F192_223gs]

no factor for k*2^203+1 in k range: 130000000000000 to 140737488355327 (250-bit factors) [mmff 0.28 mfaktc_barrett252_F192_223gs]
no factor for k*2^203+1 in k range: 140737488355328 to 281474976710655 (251-bit factors) [mmff 0.28 mfaktc_barrett252_F192_223gs]
no factor for k*2^203+1 in k range: 281474976710656 to 562949953421311 (252-bit factors) [mmff 0.28 mfaktc_barrett252_F192_223gs]

no factor for k*2^202+1 in k range: 130000000000000 to 140737488355327 (249-bit factors) [mmff 0.28 mfaktc_barrett249_F192_223gs]
no factor for k*2^202+1 in k range: 140737488355328 to 281474976710655 (250-bit factors) [mmff 0.28 mfaktc_barrett252_F192_223gs]
no factor for k*2^202+1 in k range: 281474976710656 to 562949953421311 (251-bit factors) [mmff 0.28 mfaktc_barrett252_F192_223gs]
no factor for k*2^202+1 in k range: 562949953421312 to 1125899906842623 (252-bit factors) [mmff 0.28 mfaktc_barrett252_F192_223gs]
ATH did a terrific work, taking the N ranges between 202 and 205 to their maximum allowed k limits for the actual mmff software

Now I need some volunteering effort to close the gaps of the range 200-209 and take each N to the same level...
The request is addressed to everyone,and duplicated in the "Results" thread

I know Oleg Naryshkin has been working on the range 200-249 for a long time, and will advice him as well about the change of the k limits ofthese N. Anyway, any help on these single ranges is welcome.

Luigi

p.s. just asked Oleg if he plans to update the limits, and started N=205 from 140737488355327 to 150000000000000 and N=204 from 281474976710655 to 300000000000000 using Feromant_CUDA
pps: I am also working on 201, 202 and 203 to get a "more round" k limit.

Last fiddled with by ET_ on 2019-11-23 at 10:11
ET_ is offline   Reply With Quote
Reply

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
New wanted ranges! ET_ FermatSearch 12 2016-11-09 13:31
P-1 formula (help wanted) Prime95 Data 18 2012-02-12 18:07
Most wanted kar_bon Riesel Prime Data Collecting (k*2^n-1) 15 2011-08-09 16:50
Wanted Lists R.D. Silverman Cunningham Tables 1 2010-09-21 16:16
100 Most Wanted Citrix Factoring 24 2004-02-22 01:05

All times are UTC. The time now is 02:02.

Tue Sep 22 02:02:38 UTC 2020 up 11 days, 23:13, 0 users, load averages: 1.79, 1.55, 1.51

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.