From New Scientist and NewsScan.
N.B.: Mersenne primes take the form of 2-to-the-power-of-P-minus-1, to be precise.
Michigan State University grad student Michael Shafer has succeeded in identifying the largest known prime number to date, using a distributed computer network of more than 200,000 computers located around the world. The new number is 6,320,430 digits long and is only the 40th Mersenne prime to have ever been discovered (Mersenne primes are an especially rare breed that take the form of 2-to-the-power-of-P, where P is also a prime number). Shafer was taking part in the Great Internet Mersenne Prime Search (GIMPS) project, when the new number popped up. “I had just finished meeting with my advisor when I saw the computer had found a new prime. After a short victory dance, I called up my wife and friends involved with GIMPS to share the great news,” said Shafer.
