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Old 2020-10-09, 12:46   #463
James Heinrich
 
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Quote:
Originally Posted by Ensigm View Post
Minimal TF effort aka "min. TF" as shown in the factor entry seems to be quite different from the efforts shown in the TF history entry. For example, for M113317913 the "min. TF" shows 8.4409 GHz.d, whereas the total effort up to 273 is already roughly 8.4409*2, and the TF effort in 73-74 bits is greater than 8.4409GHz-days too, considering the fact that the factor is close to 2^74. This couldn't be correct, unless the GHz-days in the factor entry and in the TF history are calibrated differently (which is also confusing).
Thanks for bringing this to my attention. The "Min. TF Effort" under the Known Factors section was being calculated incorrectly. In this particular example it was previously displaying 8.44 when it should be 30.22
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Old 2020-10-10, 13:14   #464
Viliam Furik
 
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Default Poor P-1 tool not working properly, I think

I have tried to use the tool with these search parameters:

4,000,000 - 4,999,999; Probability 0 - 10 %; Order by probability

It returns an empty table, but it shouldn't. M4087873 is listed with 2.799 % probability, meaning it should appear in the table.

If I understand the working of the tool correctly, it should return lots of exponents. If I don't, please correct me.
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Old 2020-10-10, 16:18   #465
James Heinrich
 
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Originally Posted by Viliam Furik View Post
I have tried to use the tool with these search parameters:
4,000,000 - 4,999,999; Probability 0 - 10 %; Order by probability
It returns an empty table, but it shouldn't. M4087873 is listed with 2.799 % probability, meaning it should appear in the table.
Thanks, there was a bug that prevented some exponents from appearing when they should.
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Old 2020-10-10, 17:29   #466
Ensigm
 
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Originally Posted by James Heinrich View Post
Thanks, there was a bug that prevented some exponents from appearing when they should.
There might also be a bug with LL status. If you search with parameters 4e7-5e7, 0%-10%, 1 test, more than 500 results will show up, however all exponents under 5e7 are already double-checked.

Last fiddled with by Ensigm on 2020-10-10 at 17:31
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Old 2020-10-10, 18:47   #467
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Originally Posted by Ensigm View Post
There might also be a bug with LL status.
No bug, I just don't have reliable access to that data.
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Old 2020-10-14, 15:41   #468
masser
 
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Default I broke the calculator again...

Please see the screen shot: almost every other row has strange output.

Before anyone asks, I was considering the estimate of successful trial factoring (1/bit-level) vs. the anecdotal estimate (1/100). If someone were to do tiny amounts of P-1, only reporting the factors found, could that be enough to reduce the odds of successful trial-factoring to the supposedly observed result?
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Old 2020-10-14, 16:27   #469
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Originally Posted by masser View Post
Please see the screen shot: almost every other row has strange output.
"You're not using it right"
The calculation iterates through many combinations of bounds, at each step aiming to get a bit closer at the next iteration. This works well when the process starts reasonably near the optimal bounds, it (as you can see) works very poorly (in the current implementation) when you start with bounds for ~5% and try to aim for 0.33%. I'll have to play with it and see what I can figure out. Thanks for reporting.
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Old 2020-10-14, 18:24   #470
Ensigm
 
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Quote:
Originally Posted by masser View Post
Before anyone asks, I was considering the estimate of successful trial factoring (1/bit-level) vs. the anecdotal estimate (1/100). If someone were to do tiny amounts of P-1, only reporting the factors found, could that be enough to reduce the odds of successful trial-factoring to the supposedly observed result?
"You're not doing it right"

A tiny P-1 of (B1, B2)=(9500, 143000) has a 0.33% prior possibility of finding a factor of 105000001 that is larger than 276 , according to the same tool you were using. However, to reduce the trial factoring success rate of the next bit level by 0.33% (or 0.3%), you need a P-1 run that has a prior probability of 0.33% (or 0.3%) to find a factor from 276 to 277. A P-1 run of (B1, B2)=(450368, 11259212) has a 3.22%-2.91%=0.31% probability of finding a factor in that bit range. It costs 6 GHz-days, which is quite close to a "normal" P-1, not a "tiny" one.

Conclusion: Based on calculations provided by mersenne.ca P-1 probability tool, unreported tiny P-1 runs may play a factor (no pun intended) in the phenomenon of observed TF success rate being short of prediction, but they are very unlikely to be the main reason.

Last fiddled with by Ensigm on 2020-10-14 at 18:35
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Old 2020-10-15, 18:55   #471
gLauss
 
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Default PRP for exponent not shown

M20825573 does not show my (unnecessary) PRP run, which I reported a few days ago. There seems to be a bug. Please compare the output of mersenne.ca with mersenne.org.
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Old 2020-10-15, 19:30   #472
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Originally Posted by gLauss View Post
M20825573 does not show my (unnecessary) PRP run, which I reported a few days ago. There seems to be a bug. Please compare the output of mersenne.ca with mersenne.org.
I can see it. It is in the table below the LL details.
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Old 2020-10-15, 20:26   #473
gLauss
 
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Originally Posted by Uncwilly View Post
I can see it. It is in the table below the LL details.
Yes, but it doesn't show up on the top right in "Latest Primenet details". It isn't important, but to me it looks like a bug. And I assume there are not many numbers which have both LL/DC and PRP, so it could be an interesting edge case.
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