In a classic example of the intersection between maths and news, there’s been a new Mersenne prime discovered! Mersenne primes are numbers of the form $2^p – 1$, where $p$ is a prime number. They’re highly valued as a source of large prime numbers, since testing the primality of a (suspected) prime of this form is much easier than for general prime numbers.

The new prime, which is the 48th known Mersenne prime, was found by Curtis Cooper on 25th January 2013, at the University of Central Missouri in Warrensburg, using GIMPS (the Great Internet Mersenne Prime Search) and has over 17 million digits. Cooper was also involved in the discovery of $M_{43}$ and $M_{44}$.

While Curtis has been granted a research discovery award of $3,000 by GIMPS, it doesn’t secure a cash prize from the EFF (Electronic Frontier Foundation), like the first million-digit and ten-million digit primes did ($50,000 and $100,000 respectively), or like the first 100-million digit one will when it’s found ($150,000).

If you’d like a laugh, check out the coverage on the Fox News website, which includes the gems “2 multiplied by itself 57,885,161 times, written mathematically as 2^{57,885,161}-1″ and “Prime numbers, which are divisible only by themselves and one, have little mathematical importance.” (EDIT: see comment below for an update on Fox’s article, which they’ve hastily corrected around 11am).

*via Ivars Peterson on Twitter.*

**References**

GIMPS Project Discovers Largest Known Prime Number, 2^{57,885,161}-1, announcement by GIMPS.

New 17-million-digit monster is largest known prime in *New Scientist*.

In fairness, Fox News doesn’t believe that facts are very important for journalism, so they’re consistent on that front.

The Fox News article has been unhappened. It’s now more or less a paraphrasing of the New Scientist article. The minus 1 error is still there, but the phrase about the unimportance of primes has been changed to “Though there is little mathematical value to finding a single new prime, …”

I bet they follow the Daily Mail’s model of “get any old rubbish up at first, then copy from other sources as they appear.”

Ooh, look, Slate talks about this http://www.slate.com/blogs/future_tense/2013/02/05/curtis_cooper_has_found_the_new_largest_prime_number.html (the comments range from the hilarious to the bizarre)

Although they are actually no closer to having an infinite number of primes than they where before. :)