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2020-10-19, 19:20   #12
gLauss

Nov 2014

3×13 Posts
Quote:
 Originally Posted by VBCurtis Curves at B1=50k could still find a factor, but B1=250k will have more than 5x the chance per curve (while taking about 5x as long, so odds-per-day improve).
I know. If you take a look, I did put more total effort into B1=250k curves than B1=50k. However, I ran only a few of them. According to the report_ecm, what I did in total is equivalent to 170 curves of t25. I think it is kind of unlikely for this number to have a factor less than 30 digits because of the very large P-1 bounds, too. And t35 is way beyond what I'm willing to spend on this stupid task

 2020-10-20, 08:50 #13 Viliam Furik     "Viliam Furík" Jul 2018 Martin, Slovakia 10111010102 Posts TFed to 78bits I TFed the M20825573 to 78 bits, 79 is on the way. So far, no factor.
2020-10-20, 20:18   #14
gLauss

Nov 2014

1001112 Posts

Quote:
 Originally Posted by Viliam Furik I TFed the M20825573 to 78 bits, 79 is on the way. So far, no factor.
Hihi, thanks for that! My laptop GPU is too crappy for this bitlevels. However, I assume your chances for success are quite low because of the large P-1 and the ECM curves I already ran. I won't continue on this number for now, back to boring PRP testing...

 2021-10-29, 09:31 #15 Zhangrc   "University student" May 2021 Beijing, China 2·101 Posts Factoring M19491001 I'd like to factor M19491001, just because the way it looks. I did TF to 2^75 and dozens of ECM curves because I noticed that a prior P-1 has been done. So far, no factor was found. Should I do P+1 or try P-1 with larger bounds?
 2021-10-29, 14:24 #16 VBCurtis     "Curtis" Feb 2005 Riverside, CA 7·11·67 Posts I wouldn't do another P-1 until I'd finished the B1 = 50k ECM level. I'd do a few curves at B1=250k also before repeating P-1. If I did another P-1. I'd increase the bounds by 10x or so. You have to re-do all the work of the previous P-1, so increasing bounds just a little bit means you're mostly wasting work (and thus that there are better ways to use those cycles). P+1 seems like a reasonable choice- again, pick big bounds- big enough that you won't be tempted to try even-bigger ones later. How big to pick depends quite a bit on how much effort you want to spend on this factoring effort- completing the B1=50k level is non-trivial, but completing the B1=250k level is a pretty serious effort. If you intend to go that far, choose bigger P+1 (and maybe P-1) bounds than would normally be reasonable.
2021-10-29, 14:39   #17
Viliam Furik

"Viliam Furík"
Jul 2018
Martin, Slovakia

2·373 Posts

Quote:
 Originally Posted by Zhangrc I'd like to factor M19491001, just because the way it looks. I did TF to 2^75 and dozens of ECM curves because I noticed that a prior P-1 has been done. So far, no factor was found. Should I do P+1 or try P-1 with larger bounds?
I wanted to go do TF on my new RTX 3080, but it seems I need a new version of mfaktc, compiled for CUDA runtime v11.40. So I'll do it on my RTX 2080Ti. 75 to 78 bits. See you tomorrow.

2021-11-25, 22:46   #18
gLauss

Nov 2014

3910 Posts

Quote:
 Originally Posted by VBCurtis If I did another P-1. I'd increase the bounds by 10x or so. You have to re-do all the work of the previous P-1, so increasing bounds just a little bit means you're mostly wasting work (and thus that there are better ways to use those cycles). P+1 seems like a reasonable choice- again, pick big bounds- big enough that you won't be tempted to try even-bigger ones later.
As I am stuck with "my number" and don't want to waste full t30 level, I will now run a P-1 with B1=15M and then two P+1 with B1=7.5M for 19491001. Let's see if I get lucky...

2021-11-25, 23:14   #19
Prime95
P90 years forever!

Aug 2002
Yeehaw, FL

777410 Posts

Quote:
 Originally Posted by gLauss As I am stuck with "my number" and don't want to waste full t30 level, I will now run a P-1 with B1=15M and then two P+1 with B1=7.5M for 19491001. Let's see if I get lucky...
Stop! Investigate v30.8. Wait for a future version before trying P+1.

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