Primegrid double checker prime number.

PrimeGrid’s
Generalized Fermat Prime Search
On 22 March 2017, 09:33:58 UTC, PrimeGrid’s Generalized Fermat Prime Search found the
Generalized Fermat mega prime:
2676404262144+1

The prime is 1,684,945 digits long and enters Chris Caldwell's “The Largest Known Primes
Database” (http://primes.utm.edu/primes) ranked 5th for Generalized Fermat primes and 52nd
overall. The discovery was made by Wolfgang Schwieger of Germany using an NVIDIA GeForce GTX1070 in an Intel(R) Core(TM) i7-6700K CPU at 4.00GHz with 16GB RAM, running Linux. This GPU took about 16 minutes to probable prime (PRP) test with GeneferOCL4. Wolfgang is a
member of the SETI.Germany team.

The prime was verified on 22 March 2017, 23:16:34 UTC by William de Thomas of Puerto Rico
using an NVIDIA GeForce GTX Titan X in an Intel(R) Core(TM) i7-4790K CPU at 4.00GHz with
16GB RAM, running Microsoft Windows 10 Professional Edition. This GPU took about 18
minutes to probable prime (PRP) test with GeneferOCL4. William is a member of the Puerto Rico
Assisting Science team.

The PRP was confirmed prime by an Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz with 16GB
RAM, running Microsoft Windows 10 Professional. This computer took about 8 hours 40 minutes
to complete the primality test using LLR.

The credits for the discovery are as follows:
1. Wolfgang Schwieger (Germany), discoverer
2. PrimeGrid, et al.
3. AthGFNSieve, sieve program developed by David Underbakke
4. GFNSvCUDA , sieve program developed by Anand Nair
5. GeneferOCL, probable prime program developed by Yves Gallot
6. LLR, primality program developed by Jean Penné

Entry in “The Largest Known Primes Database” can be found here:
http://primes.utm.edu/primes/page.php?id=123187

Using a single PC would have taken years to find this prime. So this timely discovery would not
have been possible without the hundreds of volunteers who contributed their spare CPU cycles. A
special thanks to everyone who offered their advice and/or computing power to the search -
especially Yves Gallot, Iain Bethune, David Underbakke, Anand Nair, Mark Rodenkirch and Geoff
Reynolds who were major forces in moving the project forward. Also, thank you to all the sievers,
especially Honza Cholt and Jim Breslin. A final thanks to Michael Goetz for porting to BOINC.
The Generalized Fermat Prime Search will continue to seek even larger primes. To join the
search please visit PrimeGrid: http://www.primegrid.com
  PrimeGrid’s PRPNet forum thread:
http://www.primegrid.com/forum_thread.php?id=1215
For more information about PrimeGrid and a complete list of available prime search projects,
please visit: http://www.primegrid.com