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09282008, 04:47 PM  #1  
 
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LOS ANGELES (AP)  Mathematicians at UCLA have discovered a 13 milliondigit prime number, a longsought milestone that makes them eligible for a $100,000 prize. The group found the 46th known Mersenne prime last month on a network of 75 computers running Windows XP. The number was verified by a different computer system running a different algorithm. "We're delighted," said UCLA's Edson Smith, the leader of the effort. "Now we're looking for the next one, despite the odds." It's the eighth Mersenne prime discovered at UCLA. Primes are numbers like three, seven and 11 that are divisible by only two whole positive numbers: themselves and one. Mersenne primes  named for their discoverer, 17thcentury French mathematician Marin Mersenne  are expressed as 2P1, or two to the power of "P" minus one. P is itself a prime number. For the new prime, P is 43,112,609. Thousands of people around the world have been participating in the Great Internet Mersenne Prime Search, a cooperative system in which underused computing power is harnessed to perform the calculations needed to find and verify Mersenne primes. The $100,000 prize is being offered by the Electronic Frontier Foundation for finding the first Mersenne prime with more than 10 million digits. The foundation supports individual rights on the Internet and set up the prime number prize to promote cooperative computing using the Web. The prize could be awarded when the new prime is published, probably next year.
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09282008, 07:38 PM  #2  
 
Cereal Eater 
that's cool! i hope they publish a website that shows every single digit (crysis for benchmarks? meh, use the 13M prime digits website!)  
09282008, 07:54 PM  #3  
 
Class 3R Laser 
so if i just randomly punch in a huge number in my calculator and try to divide it by many different numbers and they all wont evenly divide then I could win teh moneyz?
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09282008, 08:04 PM  #4  
 
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Absolutely! However, if you're going to do it by hand, you should probably pack a lunch Peace, dave
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09282008, 08:44 PM  #5  
 
Cereal Eater  Quote:
I don't think they did it randomly.. Brute force will take you years, dave gave you great advice :P  
10022008, 08:16 PM  #6  
 
Class 3R Laser Join Date: Feb 2008 Location: Houston, TX
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Mersenne primes are pretty cool. crazy useful for RSA and other factoring type algorithms yay internet encryption!  
10082008, 01:52 AM  #7  
 
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You would think the discovery of higher primes would allow them to more simply find even higher ones more quickly with the data they possess. But it sounds like it's a lot easier said than done.
 
10082008, 01:55 AM  #8  
 
Class 2M Laser Join Date: Feb 2008
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One thing that I've been pondering about this number is, is this number larger than a googolplex?
 
10082008, 02:01 AM  #9  
 
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I think that their fingers just get tired. Peace, dave
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10102008, 02:11 AM  #10  
 
Class 2M Laser Join Date: Jul 2008 Location: Central Minnesota
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10122008, 01:04 PM  #11  
 
Class 3B Laser Join Date: Dec 2007
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10142008, 11:08 AM  #12  
 
Class 2 Laser Join Date: Oct 2008 Location: Singapore
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I know one way to find prime numbers.... the sieve of eratosthenes. I'm not sure whether it'll apply to Mersenne Primes or that it'll work on large numbers easily. But I use this method quite often when finding real numbers. A googleplex may be large..... but there is a number far larger than it. I mean, u can still imagine a googleplex. It's not that hard. But for this number, you get stuck at the first step. This number is the greatest number ever used in calculation (i.e. to solve a valid problem sum, not a problem like "what's the largest number you know?" and is known as Graham's number. (I still don't have an idea of how large it is. It's really.... mindblowingly large.... and I really mean it!!!!)  
10192008, 04:15 PM  #13  
 
Class 3R Laser Join Date: Apr 2008 Location: South Florida
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About the prime number.. Wow, 13 million digits. Is this the largest prime number ever discovered (so far)? Edit: Yeah, it is.
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10202008, 03:02 PM  #14  
 
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Well, it's not hard imaginig big numbers Just picture exponential or "power towers" like 10^10^10^10^10^.....10.Then you can take the Knuth's double arrow operator 10^^10=10^10^10^10^10^10^10^10^10^10.Then extend that notation to a ntuple arrow operator 10^...^10=a big ass number whose number of digits still is enough to circle the gallaxy in nanometers ;D Of course Graham's number would need cr@p loads of terabytes just to be written in extended form.Don't wanna do any calculations now, but it's pretty possible that all the hardware storage in the world is not enough to hold every digit of this number :P  
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