mersenneforum.org Testing my numbers
 Register FAQ Search Today's Posts Mark Forums Read

 2017-04-23, 19:51 #1 Vicodin     "Anastasia" Apr 2017 Ukraine 1002 Posts Testing my numbers Hello everybody! I'm new in GIMPS. I want to know if I can test prime numbers in this program? I know some prime numbers like 2^p, where p is about several hundred billion. So testing 2^p - 1 is my dream :3 Hope my numbers are prime... :) Can I do it? Best regards, Anastasia
 2017-04-23, 20:56 #2 VictordeHolland     "Victor de Hollander" Aug 2011 the Netherlands 23×3×72 Posts Welcome to the mersenneforum! There are multiple programs available to test primality of candidate numbers. For Mersenne numbers (2^P -1, with P prime) Prime95 is the easiest to start with. You can download it from: https://www.mersenne.org/download/ You can join GIMPS if you like, a coordinated effort for finding new Mersenne primes. Testing a Mersenne candidate for primality, a so called Lucas-Lehmer test (usually shorted to LL-test) takes a couple of days on the fastest computers, to several weeks (or even months) on older models. Testing candidates with more than 100million digits takes years on a desktop computer and is not recommended if you just started. Testing billion digit numbers is not feasible with the current hardware.
 2017-04-23, 21:32 #3 kladner     "Kieren" Jul 2011 In My Own Galaxy! 236568 Posts Welcome, and Happy Number Crunching!
2017-04-23, 21:41   #4
ATH
Einyen

Dec 2003
Denmark

2×29×53 Posts

Quote:
 Originally Posted by Vicodin Hello everybody! I'm new in GIMPS. I want to know if I can test prime numbers in this program? I know some prime numbers like 2^p, where p is about several hundred billion. So testing 2^p - 1 is my dream :3 Hope my numbers are prime... :) Can I do it? Best regards, Anastasia
Unfortunately there is no program that can run a primality test on 2p-1 for p>100,000,000,000 (100 billion).

The limit for Prime95 is around 595 million, and one such test will take 6+ months even on the fastest computers, and years on "normal" computers. Mlucas might be able to go a little higher, but no where near 100 billion.

You can trial factor your number and hope to find a factor (but that will kill your dreams about the number being prime). In the "Operation Billion Digits" forum there are software like Mfactor and factor5, and I believe those can trialfactor in those ranges.

Last fiddled with by ATH on 2017-04-24 at 03:14

 2017-04-24, 01:13 #5 Uncwilly 6809 > 6502     """"""""""""""""""" Aug 2003 101×103 Posts 19×499 Posts If you are thinking of testing 2(2^127-1)-1, there is no way to test it for many, many years to come. http://mersennewiki.org/index.php/M12
2017-04-24, 01:23   #6
Prime95
P90 years forever!

Aug 2002
Yeehaw, FL

5·1,481 Posts

Quote:
 Originally Posted by Uncwilly If you are thinking of testing 2(2^127-1)-1, there is no way to test it for many, many years to come. http://mersennewiki.org/index.php/M12
That page needs updating. I thing it has been trial factored to 2^185 or so by mmff.

2017-04-24, 01:36   #7
a1call

"Rashid Naimi"
Oct 2015
Remote to Here/There

2×17×59 Posts

Quote:
 Originally Posted by Uncwilly If you are thinking of testing 2(2^127-1)-1, there is no way to test it for many, many years to come. http://mersennewiki.org/index.php/M12

Quote:
 Now it can be done on a "smart phone" in under one second.
Is that a reference to a actual app or just a computing power statement?

2017-04-24, 01:39   #8
science_man_88

"Forget I exist"
Jul 2009
Dumbassville

26×131 Posts

Quote:
 Originally Posted by Prime95 That page needs updating. I thing it has been trial factored to 2^185 or so by mmff.
think *. Also, noting that 2^1-1 is not 2, and that 2 is not a mersenne prime, and that 2^2-1 is not 7 might help.

Last fiddled with by science_man_88 on 2017-04-24 at 01:39

2017-04-24, 01:44   #9
a1call

"Rashid Naimi"
Oct 2015
Remote to Here/There

2×17×59 Posts

Quote:
 Originally Posted by science_man_88 think *. Also, noting that 2^1-1 is not 2, and that 2 is not a mersenne prime, and that 2^2-1 is not 7 might help.
Well we know who to blame:

http://mersennewiki.org/index.php?ti...action=history

 2017-04-24, 01:57 #10 a1call     "Rashid Naimi" Oct 2015 Remote to Here/There 2×17×59 Posts A search brought Nap 1 as an iphone app with arbitrary precision up to 40k and it is free.
 2017-04-24, 02:02 #11 science_man_88     "Forget I exist" Jul 2009 Dumbassville 26×131 Posts 110000T is reported as the upper k in the last posting the the operazione doppi mersenne results thread for it that I found.

 Similar Threads Thread Thread Starter Forum Replies Last Post sd235 Information & Answers 12 2018-12-06 17:56 Angular GPU Computing 13 2016-08-02 12:03 eepiccolo Math 6 2006-03-28 20:53 NeoGen Software 8 2006-03-20 01:22 sagan_fan Math 8 2002-10-09 21:20

All times are UTC. The time now is 00:08.

Wed Apr 14 00:08:52 UTC 2021 up 5 days, 18:49, 1 user, load averages: 2.42, 2.11, 1.88