mersenneforum.org Is there anyway to submit non-primes to the db?
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 2021-07-13, 22:20 #1 raresaturn   Jul 2021 416 Posts Is there anyway to submit non-primes to the db? Hi, I'm kind of new to this. I wrote a primality test program in Python and was wondering if there was any way to submit non-primes I've discovered? For example 2^85349613-1 is non-prime with a factor 318150 lines long (it's python so it doesn't give the exact number unless expanded). Might cut down some work if we can flag the non-primes. thanks
 2021-07-13, 22:27 #2 Uncwilly 6809 > 6502     """"""""""""""""""" Aug 2003 101×103 Posts 272A16 Posts 85349613 is not a prime number, thus is not part of the exponents that PrimeNet is tracking. So, you can't submit it here.
 2021-07-13, 23:07 #3 raresaturn   Jul 2021 22 Posts ah ok. What about for prime exponents?
 2021-07-13, 23:12 #4 mathwiz   Mar 2019 3×67 Posts For composite $n$ you can submit factors of $2^n-1$ to factordb.com, e.g. http://factordb.com/index.php?query=2%5E505-1. It only tracks numbers up to several million digits, so your example exponent may be too large.
 2021-07-13, 23:30 #5 mathwiz   Mar 2019 20110 Posts Also note that for composite $n$ some of the factors of $2^n-1$ are trivial to find, using the theorem here: https://en.m.wikipedia.org/wiki/Mers...ersenne_primes
 2021-07-13, 23:49 #6 Uncwilly 6809 > 6502     """"""""""""""""""" Aug 2003 101×103 Posts 2×32×557 Posts For prime exponents first look up the exponent to see if the factor is known. And look at how far the factoring has been taken to. And note that the factoring programs used are highly optimised. Also, now-a-days, factoring on a cpu is a waste of the cpu, as gpus are so much better at factoring. Yes you can submit found factors for prime exponents on the manual submissions page. Prime95 and other programs have a particular formatting that is used. I don't have the format handy. But if you look through the reference threads, linked to here: https://www.mersenneforum.org/showthread.php?t=24607 you may find it. Roughly it is Mxxxxxxxx has a factor yyyyyyyyyyyyyyyyyyyyyy Edit: Here is a line from another thread that shows a full way of submitting the data: UID: UserID/Machine, M104819381 has a factor: 574983783644612576435518337 (P-1, B1=755000, B2=20983000) The underlined bits are optional, or to be used when appropriate. Last fiddled with by Uncwilly on 2021-07-14 at 01:05
2021-07-14, 01:13   #7
raresaturn

Jul 2021

416 Posts

Quote:
 Originally Posted by Uncwilly Edit: Here is a line from another thread that shows a full way of submitting the data: UID: UserID/Machine, M104819381 has a factor: 574983783644612576435518337 (P-1, B1=755000, B2=20983000) The underlined bits are optional, or to be used when appropriate.
Thanks, but I can't find where to submit it. Does it need to be emailed or PM'd?

2021-07-14, 03:32   #8
Happy5214

"Alexander"
Nov 2008
The Alamo City

10111101112 Posts

Quote:
 Originally Posted by mathwiz For composite $n$ you can submit factors of $2^n-1$ to factordb.com, e.g. http://factordb.com/index.php?query=2%5E505-1. It only tracks numbers up to several million digits, so your example exponent may be too large.
I can confirm that the exponent the OP gave will not work with FactorDB. The limit is ~10M digits, or roughly an exponent range of ~33.2M.

Last fiddled with by Happy5214 on 2021-07-14 at 03:32 Reason: Reformat number to match

2021-07-14, 03:33   #9
Uncwilly
6809 > 6502

"""""""""""""""""""
Aug 2003
101×103 Posts

1002610 Posts

Quote:
 Originally Posted by raresaturn Thanks, but I can't find where to submit it. Does it need to be emailed or PM'd?
Quote:
 Originally Posted by Uncwilly Yes you can submit found factors for prime exponents on the manual submissions page.
.

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