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Old 2017-04-24, 03:20   #12
VBCurtis
 
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Quote:
Originally Posted by a1call View Post
A search brought Nap 1 as an iphone app with arbitrary precision up to 40k and it is free.
What are you talking about? Are you posting in the wrong thread?
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Old 2017-04-24, 04:08   #13
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Quote:
Originally Posted by VictordeHolland View Post
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.

What will you say if I have a supercomputer with 48 cores and 1 Terabyte of RAM?
I was trying to check my number on it, but my program used only 1 core :c
I don't know how to use multithreading to upgrade my algorithm :c
But I think if I do it, I will use 48 cores and it'll be more faster. My friend sais he can help me to use about 200 hundreds cores and 3 terabytes if I will have a good algorithm.
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Old 2017-04-24, 04:40   #14
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Quote:
Originally Posted by Vicodin View Post
What will you say if I have a supercomputer with 48 cores and 1 Terabyte of RAM?
I was trying to check my number on it, but my program used only 1 core :c
I don't know how to use multithreading to upgrade my algorithm :c
But I think if I do it, I will use 48 cores and it'll be more faster. My friend sais he can help me to use about 200 hundreds cores and 3 terabytes if I will have a good algorithm.
That is an impressive computer, but the answers given so far would still apply. The known algorithms would not be useful in proving your number prime in a lifetime. Unless, your algo is somehow novel and superior to best known algo which has already been stated in post that you quoted (The LL-Test),
There is a good thread which explains things very clearly. See post number 3 here:

http://www.mersenneforum.org/showthread.php?t=22047

All that aside, what kind of a computer program are you using which uses only one core of "about" 200 cores?

Is this a windows based system?

BTW, welcome to the forum.

ETA You could still, (possibly) find factors for your number, as already pointed out to you earlier.

Last fiddled with by a1call on 2017-04-24 at 04:46
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Old 2017-04-24, 04:47   #15
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I using jupyter notebook, algo "isprime" in library (Julia language). Also I work with Big Integer type for this numbers. So this program can easy output such types of numbers (less than 1 min), but it's so hard for it to work with this numbers :c
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Old 2017-04-24, 05:00   #16
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Well, I am not familiar with Julia language. Just looked it up and looks very interesting.
I am sure one of the gurus here will be able to assist you further shortly.
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Old 2017-04-24, 06:44   #17
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Quote:
Originally Posted by Vicodin View Post
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-1, where p is about several hundred billion.
So testing 2^p - 1 is my dream :3
Anastasia,

Let's compare testing prime numbers to building a house.
You think you are all set in building your dream house because you have all that is needed: a ton of cement, ten tons of bricks and twenty tons of wood ("48 cores and 1 Terabyte of RAM"). You also have a few tools: a strong power drill, a very long ruler, and a Little Giant Multi-Purpose Ladder. (that's "Julia and jupiter notebooks").

...well, that is not enough! It is not enough because you decided to skip all practicing with small houses (they are too boring, right?) - your house will be 300,000 miles high and the top levels will be reaching the moon.

Do you see? You should first get acquainted with the best known practices for best modern house construction, before dreaming about billions, alright?
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Old 2017-04-24, 07:19   #18
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Quote:
Originally Posted by Batalov View Post
Anastasia,

Let's compare testing prime numbers to building a house.
You think you are all set in building your dream house because you have all that is needed: a ton of cement, ten tons of bricks and twenty tons of wood ("48 cores and 1 Terabyte of RAM"). You also have a few tools: a strong power drill, a very long ruler, and a Little Giant Multi-Purpose Ladder. (that's "Julia and jupiter notebooks").

...well, that is not enough! It is not enough because you decided to skip all practicing with small houses (they are too boring, right?) - your house will be 300,000 miles high and the top levels will be reaching the moon.

Do you see? You should first get acquainted with the best known practices for best modern house construction, before dreaming about billions, alright?
OK. But how can I test numbers less than 595 millions?
Can I test only numbers that are offered by GIMPS or my own numbers too?
Now my computer testing a number offered by GIMPS, can I send a request to GIMPS about testing my number after my computer will have tested it's number?

Last fiddled with by Vicodin on 2017-04-24 at 07:20
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Old 2017-04-24, 09:30   #19
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Quote:
Originally Posted by science_man_88 View Post
110000T is reported as the upper k in the last posting the the operazione doppi mersenne results thread for it that I found.
Here and here is the actual limit.

You will be more than welcome if you want to close the gaps...

Regards.

Last fiddled with by ET_ on 2017-04-24 at 09:31
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Old 2017-04-25, 03:44   #20
LaurV
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Quote:
Originally Posted by science_man_88 View Post
110000T is reported as the upper k in the last posting the the operazione doppi mersenne results thread for it that I found.
Quote:
Originally Posted by ET_ View Post
Here and here is the actual limit.
Which is what George said too. 110 000 T is 59 bits for k. Which gives a q=2kp+1 which is ~bits(p)+1 longer, i.e. 60+127. That gives ~187 bits factor candidates tested.

Last fiddled with by LaurV on 2017-04-25 at 03:44
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Old 2017-05-02, 04:54   #21
Harrywill
 
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Smile Finding the prime numbers

Checking 1,2,3,4,5,6,7,... all the way up to 46 to see if 47 is prime, we need only test 2,3,5,7...... and 43

Last fiddled with by Harrywill on 2017-05-02 at 04:57
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Old 2017-05-02, 05:11   #22
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Quote:
Originally Posted by Harrywill View Post
Checking 1,2,3,4,5,6,7,... all the way up to 46 to see if 47 is prime, we need only test 2,3,5,7...... and 43
I'm not sure what prompted your comment, but you need only trial factor up to the floor of the square root of 47: 6 (or 5, since we know that 6 is composite).
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