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View Full Version : U.S. professor finds longest prime number with 17,425,170 digits



Teh One Who Knocks
02-12-2013, 11:59 AM
By Kevin Murphy | Reuters


KANSAS CITY, Missouri (Reuters) - After running 1,000 computers non-stop for 39 days to uncover the world's largest prime number yet, a Missouri college professor said this week he is starting all over to top his own record.

"It's a never-ending job," said Curtis Cooper, a computer science professor at the University of Central Missouri in Warrensburg. The computers are still running, although finding a higher prime number is estimated to take five to seven more years. Thousands of other computers in the United States are making the same search.

"This is my first love," Cooper, 60, said in an interview with Reuters. "It's pure mathematics. It's kind of an art form."

Cooper said he has received calls and emails from around the world after Wednesday's announcement that he had identified the prime number - which is a number that can only be divided by itself and 1. For example, 4 is not a prime number because it can be divided by itself, 1 and 2. Prime numbers include 2, 3, 5, 7 and on up to the giant figure Cooper and his computers discovered, which has 17,425,170 digits.

The new number is 2 multiplied by itself 57,885,161 times, minus 1. A single campus computer, labeled #22, found the number on January 25, but it had to be verified by the prime number locator project known as GIMPS - the Great Internet Mersenne Prime Search.

The term "Mersenne" refers to the rarest prime numbers, only 48 in all, that have ever been discovered. GIMPS has discovered the last 14 of them.

Working with the GIMPS system, Cooper and Central Missouri chemistry professor Steven Boone discovered two earlier record prime numbers, in 2005 and 2006. Their newest prime number is the largest discovered since 2008, at the University of California-Los Angeles. It beat the UCLA number by some 5 million digits.

Having the record prime number discovered three times at Central Missouri, a state college with about 11,000 students, is a source of great pride, said Mike Greife, the school's news bureau director. "It's kind of mind-boggling," Greife said of the search process.

Cooper said his earlier successes finding the highest prime number motivated him to keep trying. He said he spent at least two hours a day "baby-sitting" the college computers to make sure everything was operating properly. The search software runs in the background while the computers carry out other functions.

Cooper said prime numbers are mostly of interest to mathematicians, but the search has some practical uses. For one thing, it shows how computers can be used together on such a project, he said.

Prime numbers also have been used in Web applications to encrypt messages because they are so rare. Those numbers, though, have a mere 100 to 200 digits, Cooper said.

FBD
02-12-2013, 03:49 PM
17 million digits, no shit. I wonder if there is some sort of sequence. they WILL find more, I have no doubt. but it may be the sort of thing where it is an infinitely spiraling harmonic of sorts.

Acid Trip
02-12-2013, 03:59 PM
Pi has a never ending decimal and is therefore the longest prime number in existence.

What do I win?

FBD
02-12-2013, 04:01 PM
a trip to the other side of the decimal point :dance:

Teh One Who Knocks
02-12-2013, 04:03 PM
Pi has a never ending decimal and is therefore the longest prime number in existence.

What do I win?

Pi isn't a whole number :nono:

redred
02-12-2013, 04:04 PM
why ? :shrug:

Hal-9000
02-12-2013, 04:15 PM
"....this week he is starting all over to top his own record."




yeah....using 1000 computers :roll:





do it on a pad of paper you lazy %$#@@!! :x

Teh One Who Knocks
02-12-2013, 04:16 PM
"....this week he is starting all over to top his own record."




yeah....using 1000 computers :roll:





do it on a pad of paper you lazy %$#@@!! :x

You're just jealous because you don't have 1,000 computers :hand:

Acid Trip
02-12-2013, 04:20 PM
a trip to the other side of the decimal point :dance:


Pi isn't a whole number :nono:

I do not recognize the need for prime numbers to be "natural" or "counting" numbers because that's prejudice against decimals.

Take Pi and remove the decimal point. That's a whole, natural, counting number with unlimited digits.

Hal-9000
02-12-2013, 04:24 PM
You're just jealous because you don't have 1,000 computers :hand:


not yet..


:excellent:

Acid Trip
02-12-2013, 04:26 PM
not yet..


:excellent:

Just link together 12 PS3's and you'll have all the computing power you need.

Edit: Damn, never mind. One of the PS3 updates made it impossible to put a different OS on the PS3. Even if you got enough old PS3's you couldn't replace any that died.

On March 28, 2010, Sony announced it would be disabling the ability to run other operating system with the v3.21 update, due to security concerns about OtherOS. This update would not affect any existing supercomputing clusters, due to the fact that they are not connected to PSN and would not be forced to update. However, it would make replacing the individual consoles that compose the clusters very difficult if not impossible, since any newer models with the v3.21 or higher would not support Linux installation directly. This caused the end the PS3's common use for clustered computing, though there are projects like "The Condor" that were still being created with older PS3 units, and have come online after the April 1, 2010 update was released.

FBD
02-12-2013, 04:34 PM
I do not recognize the need for prime numbers to be "natural" or "counting" numbers because that's prejudice against decimals.

Take Pi and remove the decimal point. That's a whole, natural, counting number with unlimited digits.

"natural"="whole" is part of the definition.

you know how I feel about changing definitions :D

Acid Trip
02-12-2013, 04:40 PM
"natural"="whole" is part of the definition.

you know how I feel about changing definitions :D

A decimal is a female number. I mean seriously, how many males do you see with a period?

Stop being sexist towards numbers!

FBD
02-12-2013, 04:51 PM
:lol: