PrimeGrid’sExtended Sierpinski Problem Prime Search
On 25 November 2021, 03:19:26 UTC, PrimeGrid's Extended Sierpinski Problem found theMega Prime:202705*221320516+1
The prime is 6,418,121 digits long and will enter Chris Caldwell's “The Largest Known Primes
Database” (http://primes.utm.edu/primes) ranked 13th overall. This find eliminates k=202705; 8k's remain in the Extended Sierpinski Problem.
The discovery was made by Pavel Atnashev of Russia using an Intel(R) Xeon(R) E5-2695 v2
CPU @ 2.40GHz with 16GB RAM running Tiny Core Linux. This computer took about 10 hours,
59 minutes to complete the primality test using LLR2. Pavel Atnashev is a member of Ural
Federal University.

Credits for the discovery are as follows:
1.
2.
3.
4.
5.
6.

Pavel Atnashev (Russia), discoverer
PrimeGrid, et al.
Srsieve, sieving program developed by Geoff Reynolds
LLR, primality program developed by Jean Penné
LLR2, primality program developed by Pavel Atnashev
OpenPFGW, a primality program developed by Chris Nash & Jim Fougeron withmaintenance and improvements by Mark Rodenkirch

Entry in "The Largest Known Primes Database" can be found here:
https://primes.utm.edu/primes/page.php?id=133011
OpenPFGW, a primality program developed by Chris Nash & Jim Fougeron, was used to checkfor Fermat Number divisibility (including generalized and extended). For more information
about Fermat and generalized Fermat Number divisors, please see Wilfrid Keller's sites:• http://www.prothsearch.com/fermat.html• http://www.prothsearch.com/GFNfacs.html
No generalized and extended generalized Fermat number divisors were discovered with thisprime find.
Using a single PC would have taken years to find this prime. So this timely discovery would nothave been possible without the thousands of volunteers who contributed their spare CPUcycles. A special thanks to everyone who contributed their advice and/or computing power tothe search - especially all the sievers who work behind the scenes to make a find like thispossible.
The Extended Sierpinski Problem Prime Search will continue to seek even larger primes. To join
the search please visit PrimeGrid: http://www.primegrid.com

PrimeGrid’s
Extended Sierpinski Problem Prime SearchAbout PrimeGrid
PrimeGrid is a distributed computing project, developed by Rytis Slatkevičius and currently
managed by Tyler Bredl, Scott Brown, Ulrich Fries, Michael Goetz, Michael Gutierrez, DaoHeng Liu, Reginald McLean, Rytis Slatkevičius, Roman Trunov, and Christian Wallbaum.
PrimeGrid utilizes BOINC and PRPNet to search for primes with the primary goal of bringing theexcitement of prime finding to the "everyday" computer user. Simply download the software andlet 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.
BOINCThe Berkeley Open Infrastructure for Network Computing (BOINC) is a software platform
for distributed computing using volunteered computer resources. It allows users toparticipate in multiple distributed computing projects through a single program. Currently
BOINC is being developed by a team based at the University of California, Berkeley ledby David Anderson.
This platform currently supports projects from biology to math to astronomy. For more
information, please visit BOINC: http://boinc.berkeley.edu
PRPNetPRPNet is a client/server application written by Mark Rodenkirch that is specificallydesigned 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