20050115, 19:19  #1 
Dec 2004
100101011_{2} Posts 
How do I prove a 4000 digit number is prime??
I have one 31digit factor from a number of the k*2^n+1 type where n=~7300,
How do I check if the "Cofactor" is prime, it ends in ....1162049124129 Thanks 
20050115, 19:40  #2 
Dec 2004
13×23 Posts 
Not to get everyone excited I don't think the cofactor is prime, but how do I check or continue to find factors of this "cofactor"...

20050115, 20:30  #3 
Dec 2004
13×23 Posts 
I'll try
http://www.alpertron.com.ar/ECM.HTM You can put use raw interger numbers... in addition to equations. It will do a Rabin probabilistic prime check 
20050115, 21:35  #4 
Jul 2004
Potsdam, Germany
33F_{16} Posts 
Lately, I've found Primo, which seems to be a relatively fast primalty proving program for numbers of no special form.
Unfortunately, 4000 digits will most likely still take several weeks or even months. It seems like Jens Franke et. al have a distributed primalty proving program, though. 
20050509, 20:56  #5  
"Jason Goatcher"
Mar 2005
3507_{10} Posts 
Quote:
Am I breaking any laws if I use this software? Edit: I'm a US resident in Arkansas. Last fiddled with by jasong on 20050509 at 20:57 

Thread Tools  
Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Prove 2^n cannot be a perfect number  mathgrad  Homework Help  7  20160319 01:30 
How can I prove this PRP prime?  siegert81  Math  2  20141119 10:24 
62digit prime factor of a Mersenne number  ET_  Factoring  39  20060511 18:27 
The first (nonmerseinne) 10 milliondigit prime number!!!  ron29730  Miscellaneous Math  17  20040515 20:23 
How do you prove a number is prime?  Alien  Math  12  20040107 11:36 