The Electronic Frontiers Foundation was offering a $100,000 bounty on the first Marsenne prime with over 10 million digits. A Marsenne prime is a prime number of the form .
The first 10 million digit prime was discovered on August 23, 2008 by a computer at UCLA. The prime, , has 12,978,189 digits. It was discovered as part of the Great Internet Mersenne Prime Search (GIMPS). This newly-discovered prime is the 45th known Marsenne prime.
Remarkably, the 46th known Marsenne prime, which also contains more than 10 million digits, was discovered two weeks later by a computer in Germany.
There is still prize money available for the discovery of the first Marsenne primes with more than 100,000,000 and 1,000,000,000 digits!
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