PrimeGridʼs
Generalized Fermat Prime Search	  On 8 Feb 2011 09:38:57 UTC, PrimeGrid’s PRPNet found the largest known
Generalized Fermat mega prime:
145310262144+1
The prime is 1,353,265 digits long and enters Chris Caldwell's “The Largest
Known Primes Database” (http://primes.utm.edu/primes) ranked 1st for
Generalized Fermat primes and 23rd overall.
The discovery was made by Ricky L Hubbard of the United States using an AMD
PHENOM II X6 1090t @ 3.2GHz with 8GB RAM, running Windows 7. This
computer took about 11 hours to probable prime (PRP) test with GenefX64 and48 hours and 15 minutes to complete the primality test using pfgw64. Ricky is amember of the AMD Users team.
The prime was verified on 10 Feb 2011, by an Intel Q6600 @ 2.4 GHz with 2 GB
RAM, running 64 bit Windows XP Professional. This computer took a little over
50 hours 8 minutes to complete the primality test using pfgw64.
The credits for the discovery are as follows:
1. Ricky L Hubbard (United States), discoverer
2. PrimeGrid, et al.
3. AthGFNSieve, sieve program developed by David Underbakke
4. GenefX64, probable prime program developed by David Underbakke
5. PFGW, primality program developed by Chris Nash & Jim Fougeron withmaintenance and improvements by Mark Rodenkirch
Entry in “The Largest Know Primes Database” can be found here:
http://primes.utm.edu/primes/page.php?id=98160
This is only the 2nd known GFN prime at N=262144. Using a single PC would
have taken years to find this prime. So this timely discovery would not have beenpossible without the hundreds of volunteers who contributed their spare CPUcycles. A special thanks to everyone who offered their advice and/or computingpower to the search – especially David Underbakke, Mark Rodenkirch and GeoffReynolds who were major forces in moving the project forward. Also, thank you
to all the sievers, especially Honza Cholt, and PRPNet’ers who contributed to thiseffort.
This is PrimeGrid’s 9th mega prime. The Generalized Fermat Prime Search willcontinue to seek even larger primes. To join the search please visit PrimeGrid:
http://www.primegrid.com

	  About PrimeGrid

PrimeGridʼsGeneralized Fermat Prime Search

PrimeGrid is a distributed computing project, developed by Rytis Slatkevičius,Lennart Vogel, and John Blazek, which utilizes BOINC and PRPNet to search forprimes. PrimeGrid's primary goal is to bring the excitement of prime finding to the"everyday" computer user. Simply download the software and let your computer
do the rest. Participants can choose from a variety of prime forms to search. Witha little patience, you may find a large or even record breaking prime.
BOINC
The Berkeley Open Infrastructure for Network Computing (BOINC) is asoftware platform for distributed computing using volunteered computerresources. It allows users to participate in multiple distributed computing
projects through a single program. Currently BOINC is being developed bya team based at the University of California, Berkeley led by DavidAnderson.
This platform currently supports projects from biology to math to astronomy.
For more information, please visit BOINC: http://boinc.berkeley.edu
PRPNet
PRPNet is a client/server application written by Mark Rodenkirch that is
specifically designed to help find prime numbers of various forms. It is easily
ported between various OS/hardware combinations. PRPNet does not run
each PRP test itself, but relies on helper programs, such as LLR, PFGW,phrot, wwww, and genefer to do the work.
For more information, please visit 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