PrimeGrid: Mega Prime found for The Riesel Problem (Déjà vu Déjà vu)

On 31 May 2011 20:08:26 UTC, PrimeGrid’s The Riesel Problem project eliminated k=353159 by finding the mega prime: 353159*2^4331116-1The prime is 1,303,802 digits long and enters Chris Caldwell's The Largest Known Primes Database ranked 25th overall. This is the largest prime found in The Riesel Problem and PrimeGrid's 7th elimination. 57 k's now remain.The discovery was made by Jaakko Reinman (sqweeser) of Finland using an Intel Core2 Quad Q9550 @ 2.83GHz with 4 GB RAM running Linux. This computer took just over 8 hours and 9 minutes to complete the primality test using LLR. Jaakko is a member of the BOINC@Finland team.The prime was verified on 1 Jun 2011 4:05:40 UTC, by Grzegorz Granowski (Grzegorz Granowski) of Poland. For more details, please see the official announcement.

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