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发表于 2011-7-12 22:01:58
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Prime Fermat Divisor found
Congratulations to Peter Doggart (Hammeh) of the United Kingdom, the discoverer of PrimeGrid's 7th Prime Fermat Divisor in the Proth Prime Search project: 4479*2^226618+1 Divides F(226614). This is the 291st known divisor and the 8th found in 2011. Peter is a member of PrimeSearchTeam.
Official Announcement
PrimeGrid’s
Proth Prime Search
On 08 July 2011 02:22:20 UTC, PrimeGrid's Proth Prime Search project, through
PRPNet, found a prime Fermat divisor:
4479*2
226618
+1 Divides F(226614)
The prime is 68,223 digits long. It is the 8th divisor found in 2011 and 291st
overall.
The discovery was made by Peter Doggart of the United Kingdom using an AMD
Phenom 9600 X4 @ 2.3GHz with 3 GB RAM running 32 bit Windows 7. This
computer took 78 seconds to complete the primality test using LLR. Peter is a
member of the PrimeSearchTeam.
The credits for the discovery are as follows:
1. Peter Doggart (United Kingdom), discoverer
2. PrimeGrid, et al.
3. Srsieve, sieving program developed by Geoff Reynolds
4. PSieve, sieving program developed by Ken Brazier and Geoff Reynolds
5. LLR, primality program developed by Jean Penné
6. OpenPFGW, a primality program developed by Chris Nash & Jim
Fougeron with maintenance and improvements by Mark Rodenkirch
Fermat number divisibility (including generalized and extended) was checked by
OpenPFGW using the following settings: -gxo –a2 4479*2^226618+1. For more
information about Fermat and generalized Fermat number divisors, please see
Wilfrid Keller's sites:
http://www.prothsearch.net/fermat.html
http://www1.uni-hamburg.de/RRZ/W.Keller/GFNfacs.html
There were no generalized or extended generalized Fermat number divisors.
Using a single PC would have taken years to find this prime. So this timely
discovery would not have been possible without the thousands of volunteers who
contributed their spare CPU cycles. A special thanks to everyone who
contributed their advice and/or computing power to the search - especially all the
sievers who work behind the scenes to make a find like this possible.
This is PrimeGrid’s 7th prime Fermat divisor. The Proth Prime Search will
continue to search for more primes. To join the search please visit PrimeGrid:
http://www.primegrid.comPrimeGrid’s
Proth Prime Search
About PrimeGrid
PrimeGrid is a distributed computing project, developed by Rytis Slatkevičius,
Lennart Vogel, and John Blazek, which utilizes BOINC and PRPNet to search for
primes. 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. With
a little patience, you may find a large or even record breaking prime.
BOINC
The Berkeley Open Infrastructure for Network Computing (BOINC) is a
software platform for distributed computing using volunteered computer
resources. It allows users to participate in multiple distributed computing
projects through a single program. Currently BOINC is being developed by
a team based at the University of California, Berkeley led by David
Anderson.
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, 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
大意:英国的Peter Doggart发现了在PPS项目中第七个Prime Fermat Divisor 这个是第291个发现并且是2011年的第8个发现。Peter是PrimeSearchTeam的成员 |
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