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Old 2021-10-24, 19:32   #1
piforbreakfast
 
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Default DC has been completed but no factors found

So does this mean this exponent is prime now that a double-check has found no factors, or is another test still pending?

https://www.mersenne.ca/exponent/63459197

EDIT: Scratch that, does this mean then that a PRP is now needed to see if it's prime?

Last fiddled with by piforbreakfast on 2021-10-24 at 19:34
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Old 2021-10-24, 19:59   #2
petrw1
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Quote:
Originally Posted by piforbreakfast View Post
So does this mean this exponent is prime now that a double-check has found no factors, or is another test still pending?

https://www.mersenne.ca/exponent/63459197

EDIT: Scratch that, does this mean then that a PRP is now needed to see if it's prime?
Successfully Double Checked means it is verified NOT prime.
PRP is not necessary.
PRP/Cert is a recent replacement for the LL/DC tests.

A separate process can try to find factors (TF or P1 or ECM).
However, is the factors are large enough they will not be found by these methods...in the foreseen future anyway.
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Old 2021-10-24, 20:46   #3
kriesel
 
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Quote:
Originally Posted by piforbreakfast View Post
So does this mean this exponent is prime now that a double-check has found no factors, or is another test still pending?

https://www.mersenne.ca/exponent/63459197

EDIT: Scratch that, does this mean then that a PRP is now needed to see if it's prime?
Your post seems to indicate a lack of understanding of multiple fundamentals. Please read https://www.mersenneforum.org/showth...665#post521665
  1. All the exponents considered are prime. For the corresponding mersenne number to have ANY chance of being prime, the exponent must be prime. https://www.mersenneforum.org/showpo...13&postcount=4
  2. Primality tests, whether first test, double checks, triple checks, whether by LL, or by PRP of various types, do not produce factors. Standard TF or P-1 factoring or other factoring methods (P+1, ECM, rarely applied to wavefront candidates) may produce specific factors.
  3. Lucas-Lehmer test and PRP are distinct types of tests for primality. LL is conclusive if performed correctly. PRP returning a composite result is conclusive if performed correctly.
  4. Any one of the following is considered sufficient to eliminate a Mersenne number as a possible prime:
  1. a composite exponent
  2. a factor found
  3. two or more matching LL final residues >0 indicating composite, and if systematic error is ruled out, such as matching bad 0x02 residues in some previous versions of CUDALucas, CLLucas etc. (typ effort ~2.04 LL ~2.04 PRP; higher relative effort at higher exponent due to increasing error rate with run time)
  4. two or more matching PRP final residues of the same PRP type (typ effort ~2.006 PRP) indicating composite
  5. PRP/GEC/proof generation followed by successful certification (typ effort ~1.005 PRP) indicating composite
5. PRP can prove a Mersenne number composite. It does not quite prove a prime prime. It yields "proven composite" or "probably prime".
6. Any PRP test yielding "probably prime" will be considered the discovery of a new Mersenne prime, IF multiple LL tests following on different software and hardware confirm the Mersenne number is prime. Despite >120K verified PRP tests, that has not yet happened.

Last fiddled with by kriesel on 2021-10-24 at 21:43
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Old 2021-10-25, 05:51   #4
piforbreakfast
 
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Quote:
Originally Posted by kriesel View Post
Your post seems to indicate a lack of understanding of multiple fundamentals. Please read https://www.mersenneforum.org/showth...665#post521665
[LIST=1][*] All the exponents considered are prime. For the corresponding mersenne number to have ANY chance of being prime, the exponent must be prime. https://www.mersenneforum.org/showpo...13&postcount=4
You said what I meant to say. I realize all exponents must be prime, it just didn't come out that way. I appreciate the primer on primality testing and elimination.
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Old 2021-10-26, 01:40   #5
tuckerkao
 
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Quote:
Originally Posted by kriesel View Post
6. Any PRP test yielding "probably prime" will be considered the discovery of a new Mersenne prime, IF multiple LL tests following on different software and hardware confirm the Mersenne number is prime. Despite >120K verified PRP tests, that has not yet happened.[/INDENT]
If someone runs the PRP on M82,589,933, what will the result line be looking like?
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Old 2021-10-26, 01:59   #6
LaurV
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Quote:
Originally Posted by tuckerkao View Post
If someone runs the PRP on M82,589,933, what will the result line be looking like?
You can try by yourself and see. Pick a smaller exponent, like M47 or M48 or so, so you won't waste much time.
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Old 2021-10-26, 02:03   #7
tuckerkao
 
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Quote:
Originally Posted by LaurV View Post
You can try by yourself and see. Pick a smaller exponent, like M47 or M48 or so, so you won't waste much time.
The problem is that when I finish the PRP, Prime95 will upload my result to the server and add in an unnecessary result entry. I definitely don't want a PRP cert from another user too when a Mersenne number was already a proven prime.

Users can even run the PRP on an exponent with a known factor and Prime95 won't recognize it.

Last fiddled with by tuckerkao on 2021-10-26 at 02:35
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Old 2021-10-26, 02:39   #8
slandrum
 
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So don't submit the result - nothing says you have to.
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Old 2021-10-26, 05:25   #9
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Quote:
Originally Posted by LaurV View Post
You can try by yourself and see.
Depends on the app and PRP type, but:
Code:
{"exponent":"82589933", "worktype":"PRP-3", "status":"P", "program":{"name":"gpuowl", "version":"5.0-9c13870"}, "timestamp":"2018-12-26 20:15:41 UTC", "aid":"0", "fft-length":4718592, "res64":"fffffffffffffffc", "residue-type":4}
All known Mersenne primes practical have already long ago had confirming PRP/GEC runs as a reliability test of Gpuowl.
https://www.mersenneforum.org/showpo...1&postcount=13
https://www.mersenneforum.org/showpo...83&postcount=8
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Old 2021-10-26, 05:40   #10
LaurV
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Grrr...
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