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http://www.foelock.co.uk/foelock/converter/prime.htm

Ok, I can't understand wtf this guy's talkin about, but it seems interesting; he claims to have found the largest prime number (and registered it in the Guinness Book of Records)!!!

http://members.cox.net/impunity/endofworld.swf

Oh boy, I cracked up...

Chances are GIMPS (Great Internet Mercenary Prime Search) has already found that number. The largest known prime number as of now is about 10 million digits long

Look them up, if you find the next prime number with 10 million digits you could win $100,000, they give you the software and the number, all you gotta do is run it on your computer and see if it infact is a prime. That dude there is BSing

there are mathematicians and some guys called
arithmologists (from the greek arithmos which means number)
well this guy is the second one

he just "studies" behaviour of numbers and trying to
find patterns within them to develop "something"

for example he claims that if you find the relation between
to numbers when you divide them, you don't actually have
to calculate the result, just print the right sequence ..and
here is your result ..without calculating anything thus
speeding the result process

Code: Select all

/*
* Name: Prime number generator
* Copyright: Nope, it's free
* Author: Mohsen A.
* Date: 05/8/03
* Description: The name says it all
*/

#include <iostream>
#include <iomanip>
#include <fstream>
#include <cmath>

using namespace std;

int main () {

   long double loopCounter;
   long double primeCounter = 1;
   long double primeNumber = 2;
   long double numberCounter = 1;
   
   bool itsPrime = true;
   
   ofstream file;
   file.setf(ios::fixed);
   file.precision(0);
   cout.setf(ios::fixed);
   cout.precision(0);
   file.open("PrimeNumbers.txt");
   file << '1' << endl;
   cout << "Starting generation of prime numbers" << endl;
   cout << "====================================" << endl;
   while ( primeNumber > 0 ) {
       for ( loopCounter = 2; loopCounter < primeNumber; loopCounter++ ) {
           if ( fmodl(primeNumber, loopCounter) == 0 ) {
               itsPrime = false;
               break;
           }
       }
       if ( itsPrime ) {
           file << primeNumber << endl;
           cout << primeNumber << setw(5) << " is a primeNumber." << endl;
           primeCounter++;
           //cout << primeCounter << setw(5) << " primes generated so far." << endl;
       }
       itsPrime = true;
       primeNumber++;
       numberCounter++;
   }
   file.close();
   return 0;
}

Muuuuuch better than his prime number generator

Either I'm not understanding his formula or it doesn't work: <a href="http://www.foelock.co.uk/foelock/converter/images/genera3.gif">this</a>

He gives no value for n nor does he properly use sub/superscripts so I can really only guess at it what the formula really is but:

P₃ = P_{2 + 1} = Sigma(i = 1, i = n, P_i + P₂ⁱ) = (assume n = 1) P₁ + P₂¹ = 2 + 3 = 5
Ok, P₃ = 5

P₄ = P_{3 + 1} = Sigma(i = 1, i = n, P_i + P₂ⁱ) = (assume n = 2 since n = 1 will yield P₃) P₁ + P₂¹ + P₂ + P₂²= 2 + 3 + 3 + 9 = 17

But I know P₄ = 11

Perhaps somebody could explain?

Oh, the current largest known prime is 2_20996011-1.

The new largest prime was found a few weeks ago. Here's where I read the article: http://www.newscientist.com/news/news.jsp?id=ns99994438

Moshen: there's better ways to go about finding prime numbers than bruteforcing the results. To begin with, you can start with an odd number in increment by two each time, that way you don't even test to see if even numbers are prime. I know there's much more complicated methods, but that guys site seems to show a few other tricks too.

MOHSEN wrote:Chances are GIMPS (Great Internet Mercenary Prime Search) has already found that number. The largest known prime number as of now is about 10 million digits long

Look them up, if you find the next prime number with 10 million digits you could win $100,000, they give you the software and the number, all you gotta do is run it on your computer and see if it infact is a prime. That dude there is BSing

I'm 27.58% through my very first test!!!! Only been going about a month!!

But you don't get $100,000 if you find the largest - that is the prize but GIMP's take $75,000 to do other things with.

Still, $25,000 for nothing still seems a good deal....if you did find one....

Well, that's the info I got from a math teacher a couple of semesters ago. He never mentioned they take away $75,000. . . . What'd they do with it?

I think $25k goes to them against running costs, $25k goes into another prize fund......can't really remember.

Details are on their site tho

He points out that 2 and 5 are the only primes which don't recur. I don't see anything special about that since we're in base 10 (2*5)... in fact any number with factors other than 2 and 5 should recur.

from the link of Ben:

The new number is 6,320,430 digits long. It took just over two years to find using a distributed network of more than 200,000 computers.

As the author of the prime number generator on Foelock and I see that some of you are talking about my clams, I am going to try and clear some parts up. It is old hat I done this over 8 years ago.

The first thing is the prime generator II what you can download and test use the formula on that page. foelock.com/foelock/Prime/default.asp

You will see that it generates prime numbers very fast about 40,000 per second. Don’t believe me try it. foelock.com/zipped/Prime2.zip

As for my clam to the larges prime number
2^170,141,183,460,469,231,731,687,303,715,884,105,727-1
I stand by this Prime I have explained how I calculated it, and one day I will be proofed right. As it is a true Prime

I’ll try and explain the Formula to start with it don’t end up with a number it use bits true or false, if the sum of all the primes you have are true then any bit’s left must be prime.

P1 is the first prime
P2 is the second prime and so no so
P3 will be the third prime
And P22 would be the 22 prime
N = to the prime number as Pn
i = is a bit or the next prime number
If you sum all the primes and set all the bits to true if the next bit is false then it must be prime.

I do not try every prime against each number, as the next prime is a calculation of all pervious primes

I hope this help
But most likely it will die with me…

Paul

foelock wrote:I hope this help
But most likely it will die with me…

Paul

It does not have to if you can prove it. As C++ said, you can use the GIMPS software to verify that your number is indeed prime.

Further, you should take you hypothetical formula and try to prove it rigorously .
From what I've heard from you, it seems that the prime numbers set is not closed under your formula. What I'm trying to say is that your formula does not always generate a prime number. You could at best claim that it verifies prime numbers, but not that it generates them.
Which means the number you claim as the biggest prime number has to be independently verified ...

Thanks for your feedback, but If you see the txt file of primes that are generated by this formula you will see that they are all true primes, I think that’s all the proof I need that the formula works. You can download the prime generator and try it yourself, like a said if you don’t believe it try it.

Thanks Foelock