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 2022-09-24, 20:24 #23 Prime95 P90 years forever!     Aug 2002 Yeehaw, FL 3·5·72·11 Posts Finally, nailed the bugger. Starting in 30.7, the curve starting point is incorrectly computed on every curve after the first curve. This is due to "leftover state" from stage 2. The problem is lessened in 30.9 as often you'll see "switching back to FFTlen x" at the end of stage 2. I do not know how this bug impacts the success rate for ECM finding a factor.
 2022-09-25, 02:09 #24 Prime95 P90 years forever!     Aug 2002 Yeehaw, FL 3×5×72×11 Posts Download 30.9 build 2 for a fix.
 2022-09-25, 11:19 #25 ATH Einyen     Dec 2003 Denmark 23×7×61 Posts Nice work! Interesting that it could still find factors and even factors with group orders outside B1/B2. I guess the different starting points made the curves correspond to different B1/B2 values than was intended? This is just a guess. I do not really understand the math behind ECM in detail.
2022-09-25, 14:20   #26
Denial140

Dec 2021

29 Posts

Quote:
 Originally Posted by ATH I guess the different starting points made the curves correspond to different B1/B2 values than was intended? This is just a guess. I do not really understand the math behind ECM in detail.
It sounds more likely to me that the different starting points correspond to different sigma values, which change the B1/B2 required to find the factor. For any starting point, you can run the curve to any B1/B2 you want in a similar fashion to P-1.

2022-10-02, 19:24   #27
Prime95
P90 years forever!

Aug 2002
Yeehaw, FL

1F9516 Posts

Quote:

2022-10-08, 05:30   #28
bbb120

"特朗普trump"
Feb 2019

13210 Posts

Quote:
why bug can also find a factor?
maybe you can find a new algorithm by studying this "bug"

2022-10-08, 12:01   #29
charybdis

Apr 2020

53·7 Posts

Quote:
 Originally Posted by bbb120 why bug can also find a factor? maybe you can find a new algorithm by studying this "bug"
No, you can't.

ECM curves are determined by a random seed called the sigma value. The bug led to the incorrect sigma being displayed, so ECM was still being run, and was still just as likely to find a factor. Prime95 just wasn't running the exact curves it said it was running.

2022-10-10, 08:42   #30
LaurV
Romulan Interpreter

"name field"
Jun 2011
Thailand

2·47·109 Posts

Quote:
 Originally Posted by charybdis No, you can't.
Shhhh! Let him try!
You never know...

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