when does prime seach stop?

2011-08-09, 18:53

Hello.
The 4 nubers i´m working with are near 80% checked.
Does prime95 go on until 100% anyway or does it stop when the first multiplicator is found?
Thx for every answer
Simon

davieddy · 2011-08-09, 20:22

Are you factoring or LL testing?

2011-08-09, 20:39

I´m LL-testing

Christenson · 2011-08-09, 23:16

Given that you are 80% complete on your 4 exponents, and that you continue to run prime95 (or mprime), each of these exponents will finish in due time and their residues will be reported to the server and you will be able to find your name on the "top producers" list with an appropriate number of GHz-Days. Depending on how much work you want queued up at once (under options/CPU I think), a few days before each LL (or other) test completes, prime95 will contact the server and ask it for more assignments (using the worker/preferences option to decide what type), and then, when each assignment is complete, start the new assignment.

There is a slight chance (1 in 400,000) that a meteor lands on your computer and you have found the next Mersenne prime when one of those tests completes (assuming its a first-time LL test and not a double-check LL test), in which case a modicum of fame and a small amount of cash will begin moving in your direction, and the people in charge will run a double-check on your result.

This process ends when you stop it -- there are literally millions of assignments available, and plenty of other creative ways to use your CPU and/or GPU in the service of number theory to be found on this forum.

Enjoy!

Brian-E · 2011-08-09, 23:31

Quote:

Originally Posted by Unregistered

Does prime95 go on until 100% anyway or does it stop when the first multiplicator is found?

Quote:

Originally Posted by Unregistered

I´m LL-testing

It continues to 100%. The test is not looking for factors but merely determining if the number is prime or composite, and the answer to this question is not determined until the test is 100% complete.
See http://www.mersennewiki.org/index.php/Lucas-Lehmer_test for more information.

Christenson · 2011-08-10, 01:38

Thanks Brian....

Other types of tests(TF - Trial Factoring, P-1, and ECM) do stop after finding the first factor when they do find factors; on average, they don't find factors and run to completion but they do so often enough that they reduce the total amount of LL testing required.

2011-08-09, 18:53	#1
Unregistered 8,273 Posts	when does prime seach stop? Hello. The 4 nubers i´m working with are near 80% checked. Does prime95 go on until 100% anyway or does it stop when the first multiplicator is found? Thx for every answer Simon

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2011-08-09, 20:22	#2
davieddy "Lucan" Dec 2006 England 1100101001010₂ Posts	Are you factoring or LL testing?

2011-08-09, 20:39	#3
Unregistered 3·5·449 Posts	I´m LL-testing

2011-08-09, 23:16	#4
Christenson Dec 2010 Monticello 5·359 Posts	Given that you are 80% complete on your 4 exponents, and that you continue to run prime95 (or mprime), each of these exponents will finish in due time and their residues will be reported to the server and you will be able to find your name on the "top producers" list with an appropriate number of GHz-Days. Depending on how much work you want queued up at once (under options/CPU I think), a few days before each LL (or other) test completes, prime95 will contact the server and ask it for more assignments (using the worker/preferences option to decide what type), and then, when each assignment is complete, start the new assignment. There is a slight chance (1 in 400,000) that a meteor lands on your computer and you have found the next Mersenne prime when one of those tests completes (assuming its a first-time LL test and not a double-check LL test), in which case a modicum of fame and a small amount of cash will begin moving in your direction, and the people in charge will run a double-check on your result. This process ends when you stop it -- there are literally millions of assignments available, and plenty of other creative ways to use your CPU and/or GPU in the service of number theory to be found on this forum. Enjoy!

2011-08-10, 01:38	#6
Christenson Dec 2010 Monticello 5·359 Posts	Thanks Brian.... Other types of tests(TF - Trial Factoring, P-1, and ECM) do stop after finding the first factor when they do find factors; on average, they don't find factors and run to completion but they do so often enough that they reduce the total amount of LL testing required.