PrimeGrid: SR5 Mega Prime - January 2016 Edition

On 11 January 2016, 10:02:08 UTC, PrimeGrid’s Sierpinski/Riesel Base 5 Problem project eliminated k=306398 by finding the mega prime: 306398*5^2112410-1 The prime is 1,476,517 digits long and enters Chris Caldwell's The Largest Known Primes Database ranked 50th overall. This is the largest known base 5 mega prime. 77 k's now remain in the Riesel Base 5 Problem. The discovery was made by André Ahlfors Dahl (NocFlame) of Sweden using an Intel(R) Xeon(R) CPU W3520 @ 2.67GHz with 16GB RAM running Linux. This computer took about 77 hours 10 minutes to complete the primality test using LLR. André is a member of the Gridcoin team. The prime was verified on 17 January 2016, 19:36:26 UTC by evaotaku00 of the United States using an Intel(R) Xeon(R) CPU X5355 @ 2.66GHz with 24GB RAM running Darwin. This computer took about 77 hours 10 minutes to complete the primality test using LLR. evaotaku00 is a member of the Ars Technica team. For more details, please see the official announcement.

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