20211024, 19:32  #1 
Oct 2020
Terre Haute, IN
2^{5}·3 Posts 
DC has been completed but no factors found
So does this mean this exponent is prime now that a doublecheck 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 20211024 at 19:34 
20211024, 19:59  #2  
1976 Toyota Corona years forever!
"Wayne"
Nov 2006
Saskatchewan, Canada
2^{3}·3·199 Posts 
Quote:
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. 

20211024, 20:46  #3  
"TF79LL86GIMPS96gpu17"
Mar 2017
US midwest
13261_{8} Posts 
Quote:
5. PRP can prove a Mersenne number composite. It does not quite prove a prime prime. It yields "proven composite" or "probably prime". Last fiddled with by kriesel on 20211024 at 21:43 

20211025, 05:51  #4  
Oct 2020
Terre Haute, IN
60_{16} Posts 
Quote:


20211026, 01:40  #5  
"Tucker Kao"
Jan 2020
Head Base M168202123
502_{10} Posts 
Quote:


20211026, 01:59  #6 
Romulan Interpreter
"name field"
Jun 2011
Thailand
3^{4}×11^{2} Posts 

20211026, 02:03  #7  
"Tucker Kao"
Jan 2020
Head Base M168202123
2·251 Posts 
Quote:
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 20211026 at 02:35 

20211026, 02:39  #8 
Jan 2021
California
11100100_{2} Posts 
So don't submit the result  nothing says you have to.

20211026, 05:25  #9 
"TF79LL86GIMPS96gpu17"
Mar 2017
US midwest
37×157 Posts 
Depends on the app and PRP type, but:
Code:
{"exponent":"82589933", "worktype":"PRP3", "status":"P", "program":{"name":"gpuowl", "version":"5.09c13870"}, "timestamp":"20181226 20:15:41 UTC", "aid":"0", "fftlength":4718592, "res64":"fffffffffffffffc", "residuetype":4} https://www.mersenneforum.org/showpo...1&postcount=13 https://www.mersenneforum.org/showpo...83&postcount=8 
20211026, 05:40  #10 
Romulan Interpreter
"name field"
Jun 2011
Thailand
3^{4}×11^{2} Posts 
Grrr...

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