Jump to content
Sign in to follow this  

World record ($100,000) prime number found?

1 post in this topic

Recommended Posts


Researchers may have turned up the 45th example of a Mersenne prime—a type of prime number rare enough that months or years of computerized searching are required to pick one out among the throngs of mere primes.

Details are still sketchy but the Great Internet Mersenne Prime Search (GIMPS) has announced on its Web site that a computer turned up a candidate Mersenne (pronounced mehr-SENN) prime on August 23. Checking began this week and should be completed by September 16.

If it checks out, the finding of the 45th Mersenne prime (MP) might qualify for a $100,000 prize offered by the Electronic Frontier Foundation for anyone who a prime number having at least 10 million digits. The 44th MP, discovered in September 2006 by two researchers at Central Missouri State University, clocked in at 9.808358 million digits.

Mersennse primes, named for 17th-century French smarty-pants monk Marin Mersenne (left), follow the formula 2^p – 1, where the power p is itself a prime number. (Commenters, don't hesitate to pounce on errors in my arithmetic.) Take p=3:

2^3 – 1

= 8 – 1

= 7, which is prime


But not all p's yield the Mersenne variety.

Consider p=11:

2^11 – 1

= 2048 – 1

= 2047

= 23 * 89

(T4P = thanks for playing)

The 44th MP had p of 32,582,657.

People aren't hunting for Mersenne primes in order to prove anything about them, according to Mike Breen of the American Mathematical Society. "They're doing it because it's there, and it's an interesting challenge," he says. Math nerds also go ga-ga for really big numbers, as we all do I'm sure.

Here's a side note courtesy of Breen (to whom no errors of mine should be attributed): Mersenne primes are all associated with "perfect numbers," those such as 6 or 28 whose factors add up to themselves (or to double themselves if you include the number itself as a factor). E.g., the factors of 28 are 1, 2, 4, 7 and 14, which add up to 28.

There's a simple formula relating the two:

Perfect Number = MP * 2^(p-1)

Take p=3 again:

(2^3 – 1) * (2^[3-1])

= 7 * 2^2

= 7 * 4

= 28

I leave the proof of the relationship to the reader.


Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  
- Back to Top -

Important Disclaimer: Please read carefully the Visajourney.com Terms of Service. If you do not agree to the Terms of Service you should not access or view any page (including this page) on VisaJourney.com. Answers and comments provided on Visajourney.com Forums are general information, and are not intended to substitute for informed professional medical, psychiatric, psychological, tax, legal, investment, accounting, or other professional advice. Visajourney.com does not endorse, and expressly disclaims liability for any product, manufacturer, distributor, service or service provider mentioned or any opinion expressed in answers or comments. VisaJourney.com does not condone immigration fraud in any way, shape or manner. VisaJourney.com recommends that if any member or user knows directly of someone involved in fraudulent or illegal activity, that they report such activity directly to the Department of Homeland Security, Immigration and Customs Enforcement. You can contact ICE via email at Immigration.Reply@dhs.gov or you can telephone ICE at 1-866-347-2423. All reported threads/posts containing reference to immigration fraud or illegal activities will be removed from this board. If you feel that you have found inappropriate content, please let us know by contacting us here with a url link to that content. Thank you.