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Old 2018-05-06, 19:05   #232
GP2
 
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Quote:
Originally Posted by GP2 View Post
At the very least, the log file recorded the wrong exponent; however it seems quite plausible that the interim residue sent to the server was also associated with the wrong exponent.
This is happening fairly often.

For example I'm running triple-check LL tests in the 2M range just for fun, and there are hundreds of examples of the above bug.

For instance:

Code:
[Sun May 06 17:47:58 2018 - ver 29.4]
Sending interim residue 500000 for M2331421
Sending result to server: UID: GP2/old, M2331379 is not prime. Res64: ...

PrimeNet success code with additional info:
LL result matches previously verified M2331379 --
CPU credit is 0.1575 GHz-days.



[Sun May 06 18:03:14 2018 - ver 29.4]
Sending interim residue 500000 for M2331421
Sending result to server: UID: GP2/old, M2331421 is not prime. Res64: ...

PrimeNet success code with additional info:
LL result matches previously verified M2331421 --
CPU credit is 0.1575 GHz-days.

Once again, the interim residue result is not sent immediately, but rather is stored in prime.spl and only gets sent when the LL test completes, and a new LL test starts.

When this happens, prime.log sometimes records the wrong exponent. The first "Sending interim residue" line above should state that it's for M2331379, not M2331421.

Is this error only present in the logging within prime.log, or is the wrong exponent actually being sent to Primenet?

Can we check if Primenet recorded two different interim residues for 500000 for M2331421, and none for M2331379? If so, there could be a lot of bad interim residues in the database by now.
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Old 2018-05-07, 00:23   #233
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I've added the interim residues bug to my to-do list. I'm buried in AVX512 development right now so I won't get to it soon. Anyway, the server isn't using interim residues right now and for LL tests which take several days, the server should be getting several good interim residues per LL test.
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Old 2018-05-07, 17:05   #234
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Quote:
Originally Posted by Prime95 View Post
I've added the interim residues bug to my to-do list. I'm buried in AVX512 development right now so I won't get to it soon. Anyway, the server isn't using interim residues right now and for LL tests which take several days, the server should be getting several good interim residues per LL test.
Under what circumstances do results get buffered into a prime.spl file rather than being sent to Primenet immediately? I wonder if this occasionally happens for final LL residues and not just for interim residues.
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Old 2018-05-07, 17:57   #235
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Quote:
Originally Posted by GP2 View Post
Under what circumstances do results get buffered into a prime.spl file rather than being sent to Primenet immediately? I wonder if this occasionally happens for final LL residues and not just for interim residues.
Important messages are sent immediately. Interim residues are spooled for later (the daily checkin). So the bug could be affecting the last interim LL residue.
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Old 2018-05-11, 03:12   #236
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Is it possible to do trial factoring on non-base 2 numbers e.g. 3^p+-1 using Prime95? Thanks.
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Old 2018-05-11, 03:20   #237
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Quote:
Originally Posted by Citrix View Post
Is it possible to do trial factoring on non-base 2 numbers e.g. 3^p+-1 using Prime95? Thanks.
Um, no. There should be several good sievers out there that do what you need.
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Old 2018-05-11, 03:24   #238
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Unfortunately there aren't any.
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Old 2018-05-11, 05:52   #239
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srxsieve does k*b^n+-1. You want k = 1, no?
Not sure if sr1sieve will do +1 and -1 at the same time; you might have to run two instances.
Or do you mean sieve the cofactors after dividing out all the evens?
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Old 2018-05-11, 06:28   #240
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Quote:
Originally Posted by VBCurtis View Post
srxsieve does k*b^n+-1. You want k = 1, no?
Not sure if sr1sieve will do +1 and -1 at the same time; you might have to run two instances.
Or do you mean sieve the cofactors after dividing out all the evens?
These numbers have the same(-ish) factor restrictions (2kp+1) as Mersennes, and hence should be TF-ed, not sieved. Mfaktc could be modified to handle these, I guess, with a little bit of work. IIRC, mfaktc was already modified to handle Wagstaff numbers ((2^p+1)/3).

EDIT:- The rule seems to be f = 1 or 7 (mod 12) for (3^p+1)/4, and f = 1 or 11 (mod 12) for (3^p-1)/2

Last fiddled with by axn on 2018-05-11 at 06:35
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Old 2018-05-11, 20:46   #241
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How can I manually do a PRP-CF?
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Old 2018-05-12, 02:15   #242
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Quote:
Originally Posted by heliosh View Post
How can I manually do a PRP-CF?
At present, the only way is to get PRP-CF assignments using prime95/mprime.

You could configure a prime95 with an internet connection to get several weeks ow PRP-CF work and then move the worktodo.txt file to your target machine.
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