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2018-08-04, 19:58   #23
rogue

"Mark"
Apr 2003
Between here and the

22×1,481 Posts

Quote:
 Originally Posted by ET_ 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.

 2018-08-13, 12:55 #24 rogue     "Mark" Apr 2003 Between here and the 22×1,481 Posts 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
 2018-08-19, 21:54 #25 rogue     "Mark" Apr 2003 Between here and the 22×1,481 Posts 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
 2018-12-13, 16:52 #26 rogue     "Mark" Apr 2003 Between here and the 22·1,481 Posts 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.
2019-11-22, 10:14   #27
ET_
Banned

"Luigi"
Aug 2002
Team Italia

476610 Posts
Some new "Most wanted" ranges

Quote:
 Originally Posted by ATH 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...

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

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