PrimeGride News

[Dirk Broer]

PrimeGrid: World Record Sophie Germain Prime!
On 29 February 2016 05:39:14 UTC, PrimeGrid’s Sophie Germain Prime Search found a World Record Sophie Germain prime: 2618163402417*2^1290000-1 (2p+1: 2618163402417*2^1290001-1 )

The prime is 388,342 digits long, eclipsing the previous record of 200,701 digits. It enters Chris Caldwell's “The Largest Known Primes Database ” ranked 1st for Sophie Germain primes and 3,747th overall.

The discovery was made by Scott Brown (Scott Brown ) of the United States using an Intel(R) Core(TM)2 Quad CPU Q6700 @ 2.66GHz with 4 GB RAM running Microsoft Windows 7 Enterprise. This computer, using LLR, took about 1 hour and 33 minutes to complete the primality test. Scott is a member of the Duke University team.

The prime was verified on 29 February 2016 06:21:47 UTC, by Vaughan Davies (vaughan ) of Australia using an Intel(R) Core(TM) i7-4770S CPU @ 3.10GHz with 32 GB RAM running Microsoft Windows 7 Ultimate. This computer, using LLR, took about 47 minutes to complete the primality test. Vaughan is a member of the AMD Users team.

For more details, please see the official announcement.
6-3-2016 14:50:22

[NeoGen]

Aww Vaughan... had you been just a tad quicker you could have been the one submitting the original prime, instead of verification. The difference was less than an hour!

Oh well... You'll catch the next one

[AMDave]

I'd still be happy with a verification mention
Vaughan still has 10 in the current list of the top 5000 Titans with one of those now just outside the top 100 (much higher than the one he just verified)

-----  -------------------------------- -------
 rank           description              digits
-----  -------------------------------- -------
  105  29*920^367810-1                  1090113

There are plenty more out there. You might get the next one a few minutes from now!

[vaughan]

Very true Dave. It was found right near the end of the February challenge at PG. Soon after I switched most of my CPUs to a mix of other projects. There are still some badges I want to achieve in PG so I'll crunch some more tasks there.

[vaughan]

I don't think I've seen this before: PrimeGrid's website is down.