## Other

drummers-lowrise

PrimeGrid's primary goal is to advance mathematics by enabling everyday computer users to contribute their system's processing power towards prime finding. By simply downloading and installing BOINC and attaching to the PrimeGrid project, 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 and enter into Chris Caldwell's The Largest Known Primes Database as a Titan!

PrimeGrid's secondary goal is to provide relevant educational materials about primes. Additionally, we wish to contribute to the field of mathematics.

Lastly, primes play a central role in the cryptographic systems which are used for computer security. Through the study of prime numbers it can be shown how much processing is required to crack an encryption code and thus to determine whether current security schemes are sufficiently secure.

PrimeGrid is currently running several sub-projects:
• 321 Prime Search: searching for mega primes of the form 3·2n±1.
• Cullen-Woodall Search: searching for mega primes of forms n·2n+1 and n·2n−1.
• Extended Sierpinski Problem: helping solve the Extended Sierpinski Problem.
• Generalized Fermat Prime Search: searching for megaprimes of the form b2n+1.
• Prime Sierpinski Project: helping Prime Sierpinski Project solve the Prime Sierpinski Problem.
• Proth Prime Search: searching for primes of the form k·2n+1.
• Seventeen or Bust: helping to solve the Sierpinski Problem.
• Sierpinski/Riesel Base 5: helping to solve the Sierpinski/Riesel Base 5 Problem.
• Sophie Germain Prime Search: searching for primes p and 2p+1.
• The Riesel problem: helping to solve the Riesel Problem.
You can choose the projects you would like to run by going to the project preferences page.

## Recent Significant Primes

On 29 June 2019, 00:54:18 UTC, PrimeGrid's Generalized Fermat Prime Search found the Generalized Fermat mega prime:
2877652524288+1
The prime is 3,386,397 digits long and enters Chris Caldwell's The Largest Known Primes Database ranked 3rd for Generalized Fermat primes and 26th overall.

The discovery was made by Roman Vogt (Tabaluga) of Germany using an NVIDIA GeForce GTX 1060 in an Intel(R) Core(TM) i7-2700K CPU @ 3.50GHz CPU with 16GB RAM, running Windows 10. This computer took about 1 hour and 42 minutes to probable prime (PRP) test with GeneferOCL5. Roman is a member of the Sicituradastra. team.

The PRP was confirmed prime by an Intel(R) Xeon(R) CPU E3-1240 v6 @ 3.70GHz with 4GB RAM, running Linux. This computer took about 25 hours 53 minutes to complete the primality test using multithreaded LLR.

On 23 June 2019, 14:39:48 UTC, PrimeGrid's Sierpiński/Riesel Base 5 Problem project eliminated k=322498 by finding the mega prime:
322498·52800819-1
The prime is 1,957,694 digits long and enters Chris Caldwell's The Largest Known Primes Database ranked 63rd overall and is the largest known base 5 prime. 67 k's now remain in the Riesel Base 5 problem.

The discovery was made by Jordan Romaidis of the United States using an Intel(R) Xeon(R) Gold 5120 CPU @ 2.20GHz with 96GB RAM running Microsoft Windows 10 Enterprise x64 Edition. This computer took about 25 hours and 28 minutes to primality test using multithreaded LLR. Jordan is a member of the San Francisco team. For more information, please see the Official Announcement.

On 21 June 2019, 01:30:42 UTC, PrimeGrid's Sierpiński/Riesel Base 5 Problem project eliminated k=88444 by finding the mega prime:
88444·52799269-1
The prime is 1,956,611 digits long and enters Chris Caldwell's The Largest Known Primes Database ranked 63rd overall and is the largest known base 5 prime. 68 k's now remain in the Riesel Base 5 problem.

The discovery was made by Scott Brown of the United States using an Intel(R) Core(TM) i7-8700 CPU @ 3.20GHz with 32GB RAM running Microsoft Windows 10 Professional x64 Edition. This computer took about 5 hours and 29 minutes to primality test using multithreaded LLR. Scott is a member of the Aggie The Pew team. For more information, please see the Official Announcement.

### Other significant primes

3·211895718-1 (321): official announcement | 321
3·211731850-1 (321): official announcement | 321
3·211484018-1 (321): official announcement | 321
3·210829346+1 (321): official announcement | 321
3·27033641+1 (321): official announcement | 321
3·26090515-1 (321): official announcement | 321
3·25082306+1 (321): official announcement | 321
3·24235414-1 (321): official announcement | 321
3·22291610+1 (321): official announcement | 321

27·27046834+1 (27121): official announcement | 27121
27·25213635+1 (27121): official announcement | 27121
27·24583717-1 (27121): official announcement | 27121
27·24542344-1 (27121): official announcement | 27121
121·24553899-1 (27121): official announcement | 27121
27·23855094-1 (27121): official announcement | 27121

48277590120607451+37835074*23#*n for n=0..25 (AP26): official announcement
142099325379199423+16549135*23#*n for n=0..25 (AP26): official announcement
149836681069944461+7725290*23#*n for n=0..25 (AP26): official announcement
43142746595714191+23681770*23#*n for n=0..25 (AP26): official announcement

6679881·26679881+1 (CUL): official announcement | Cullen
6328548·26328548+1 (CUL): official announcement | Cullen

193997·211452891+1 (ESP): official announcement | k=193997 eliminated
161041·27107964+1 (ESP): official announcement | k=161041 eliminated

147855!-1 (FPS): official announcement | Factorial
110059!+1 (FPS): official announcement | Factorial
103040!-1 (FPS): official announcement | Factorial
94550!-1 (FPS): official announcement | Factorial

1806676·411806676+1 (GC): official announcement | Generalized Cullen
1323365·1161323365+1 (GC): official announcement | Generalized Cullen
1341174·531341174+1 (GC): official announcement | Generalized Cullen
682156·79682156+1 (GC): official announcement | Generalized Cullen
427194·113427194+1 (GC): official announcement | Generalized Cullen

10590941048576+1 (GFN): official announcement | Generalized Fermat Prime
9194441048576+1 (GFN): official announcement | Generalized Fermat Prime
2877652524288+1 (GFN): official announcement | Generalized Fermat Prime
2788032524288+1 (GFN): official announcement | Generalized Fermat Prime
2733014524288+1 (GFN): official announcement | Generalized Fermat Prime
2312092524288+1 (GFN): official announcement | Generalized Fermat Prime
2061748524288+1 (GFN): official announcement | Generalized Fermat Prime
1880370524288+1 (GFN): official announcement | Generalized Fermat Prime
475856524288+1 (GFN): official announcement | Generalized Fermat Prime
356926524288+1 (GFN): official announcement | Generalized Fermat Prime
341112524288+1 (GFN): official announcement | Generalized Fermat Prime
75898524288+1 (GFN): official announcement | Generalized Fermat Prime
6291332262144+1 (GFN): official announcement | Generalized Fermat Prime
6287774262144+1 (GFN): official announcement | Generalized Fermat Prime
5828034262144+1 (GFN): official announcement | Generalized Fermat Prime
5205422262144+1 (GFN): official announcement | Generalized Fermat Prime
5152128262144+1 (GFN): official announcement | Generalized Fermat Prime
4489246262144+1 (GFN): official announcement | Generalized Fermat Prime
4246258262144+1 (GFN): official announcement | Generalized Fermat Prime
3933508262144+1 (GFN): official announcement | Generalized Fermat Prime
3853792262144+1 (GFN): official announcement | Generalized Fermat Prime
3673932262144+1 (GFN): official announcement | Generalized Fermat Prime
3596074262144+1 (GFN): official announcement | Generalized Fermat Prime
3547726262144+1 (GFN): official announcement | Generalized Fermat Prime
3060772262144+1 (GFN): official announcement | Generalized Fermat Prime
2676404262144+1 (GFN): official announcement | Generalized Fermat Prime
2611204262144+1 (GFN): official announcement | Generalized Fermat Prime
2514168262144+1 (GFN): official announcement | Generalized Fermat Prime
2042774262144+1 (GFN): official announcement | Generalized Fermat Prime
1828858262144+1 (GFN): official announcement | Generalized Fermat Prime
1615588262144+1 (GFN): official announcement | Generalized Fermat Prime
1488256262144+1 (GFN): official announcement | Generalized Fermat Prime
1415198262144+1 (GFN): official announcement | Generalized Fermat Prime
773620262144+1 (GFN): official announcement | Generalized Fermat Prime
676754262144+1 (GFN): official announcement | Generalized Fermat Prime
525094262144+1 (GFN): official announcement | Generalized Fermat Prime
361658262144+1 (GFN): official announcement | Generalized Fermat Prime
145310262144+1 (GFN): official announcement | Generalized Fermat Prime
40734262144+1 (GFN): official announcement | Generalized Fermat Prime
47179704131072+1 (GFN): official announcement | Generalized Fermat Prime
47090246131072+1 (GFN): official announcement | Generalized Fermat Prime
46776558131072+1 (GFN): official announcement | Generalized Fermat Prime
46736070131072+1 (GFN): official announcement | Generalized Fermat Prime
46730280131072+1 (GFN): official announcement | Generalized Fermat Prime
46413358131072+1 (GFN): official announcement | Generalized Fermat Prime
46385310131072+1 (GFN): official announcement | Generalized Fermat Prime
46371508131072+1 (GFN): official announcement | Generalized Fermat Prime
46077492131072+1 (GFN): official announcement | Generalized Fermat Prime
45570624131072+1 (GFN): official announcement | Generalized Fermat Prime
45315256131072+1 (GFN): official announcement | Generalized Fermat Prime
44919410131072+1 (GFN): official announcement | Generalized Fermat Prime
44438760131072+1 (GFN): official announcement | Generalized Fermat Prime
44330870131072+1 (GFN): official announcement | Generalized Fermat Prime
44085096131072+1 (GFN): official announcement | Generalized Fermat Prime
44049878131072+1 (GFN): official announcement | Generalized Fermat Prime
43165206131072+1 (GFN): official announcement | Generalized Fermat Prime
43163894131072+1 (GFN): official announcement | Generalized Fermat Prime
42654182131072+1 (GFN): official announcement | Generalized Fermat Prime

563528·13563528-1 (GW): official announcement | Generalized Woodall
404882·43404882-1 (GW): official announcement | Generalized Woodall

1098133#-1 (PRS): official announcement | Primorial
843301#-1 (PRS): official announcement | Primorial

373·23404702+1 (MEGA): official announcement | Mega Prime
303·23391977+1 (MEGA): official announcement | Mega Prime
369·23365614+1 (MEGA): official announcement | Mega Prime
393·23349525+1 (MEGA): official announcement | Mega Prime
113·23437145+1 (MEGA): official announcement | Mega Prime
159·23425766+1 (MEGA): official announcement | Mega Prime
245·23411973+1 (MEGA): official announcement | Mega Prime
177·23411847+1 (MEGA): official announcement | Mega Prime
35·23587843+1 (MEGA): official announcement | Mega Prime
35·23570777+1 (MEGA): official announcement | Mega Prime
33·23570132+1 (MEGA): official announcement | Mega Prime
93·23544744+1 (MEGA): official announcement | Mega Prime
87·23496188+1 (MEGA): official announcement | Mega Prime
51·23490971+1 (MEGA): official announcement | Mega Prime
81·23352924+1 (MEGA): official announcement | Mega Prime

1155·23455254+1 (PPS-Mega): official announcement | Mega Prime
1065·23447906+1 (PPS-Mega): official announcement | Mega Prime
1155·23446253+1 (PPS-Mega): official announcement | Mega Prime
943·23442990+1 (PPS-Mega): official announcement | Mega Prime
943·23440196+1 (PPS-Mega): official announcement | Mega Prime
543·23438810+1 (PPS-Mega): official announcement | Mega Prime
625·23438572+1 (PPS-Mega): official announcement | Mega Prime
1147·23435970+1 (PPS-Mega): official announcement | Mega Prime
911·23432643+1 (PPS-Mega): official announcement | Mega Prime
1127·23427219+1 (PPS-Mega): official announcement | Mega Prime
1119·23422189+1 (PPS-Mega): official announcement | Mega Prime
1005·23420846+1 (PPS-Mega): official announcement | Mega Prime
975·23419230+1 (PPS-Mega): official announcement | Mega Prime
999·23418885+1 (PPS-Mega): official announcement | Mega Prime
907·23417890+1 (PPS-Mega): official announcement | Mega Prime
953·23405729+1 (PPS-Mega): official announcement | Mega Prime
833·23403765+1 (PPS-Mega): official announcement | Mega Prime
1167·23399748+1 (PPS-Mega): official announcement | Mega Prime
611·23398273+1 (PPS-Mega): official announcement | Mega Prime
609·23392301+1 (PPS-Mega): official announcement | Mega Prime
1049·23395647+1 (PPS-Mega): official announcement | Mega Prime
555·23393389+1 (PPS-Mega): official announcement | Mega Prime
805·23391818+1 (PPS-Mega): official announcement | Mega Prime
663·23390469+1 (PPS-Mega): official announcement | Mega Prime
621·23378148+1 (PPS-Mega): official announcement | Mega Prime
1093·23378000+1 (PPS-Mega): official announcement | Mega Prime
861·23377601+1 (PPS-Mega): official announcement | Mega Prime
677·23369115+1 (PPS-Mega): official announcement | Mega Prime
715·23368210+1 (PPS-Mega): official announcement | Mega Prime
617·23368119+1 (PPS-Mega): official announcement | Mega Prime
777·23367372+1 (PPS-Mega): official announcement | Mega Prime
533·23362857+1 (PPS-Mega): official announcement | Mega Prime
619·23362814+1 (PPS-Mega): official announcement | Mega Prime
1183·23353058+1 (PPS-Mega): official announcement | Mega Prime
543·23351686+1 (PPS-Mega): official announcement | Mega Prime
733·23340464+1 (PPS-Mega): official announcement | Mega Prime
651·23337101+1 (PPS-Mega): official announcement | Mega Prime
849·23335669+1 (PPS-Mega): official announcement | Mega Prime
611·23334875+1 (PPS-Mega): official announcement | Mega Prime
673·23330436+1 (PPS-Mega): official announcement | Mega Prime
655·23327518+1 (PPS-Mega): official announcement | Mega Prime
659·23327371+1 (PPS-Mega): official announcement | Mega Prime
821·23327003+1 (PPS-Mega): official announcement | Mega Prime
555·23325925+1 (PPS-Mega): official announcement | Mega Prime
791·23323995+1 (PPS-Mega): official announcement | Mega Prime
597·23322871+1 (PPS-Mega): official announcement | Mega Prime
415·23559614+1 (PPS-Mega): official announcement | Mega Prime
465·23536871+1 (PPS-Mega): official announcement | Mega Prime
447·23533656+1 (PPS-Mega): official announcement | Mega Prime
495·23484656+1 (PPS-Mega): official announcement | Mega Prime
491·23473837+1 (PPS-Mega): official announcement | Mega Prime
453·23461688+1 (PPS-Mega): official announcement | Mega Prime
479·23411975+1 (PPS-Mega): official announcement | Mega Prime
453·23387048+1 (PPS-Mega): official announcement | Mega Prime
403·23334410+1 (PPS-Mega): official announcement | Mega Prime
309·23577339+1 (PPS-Mega): official announcement | Mega Prime
381·23563676+1 (PPS-Mega): official announcement | Mega Prime
351·23545752+1 (PPS-Mega): official announcement | Mega Prime
345·23532957+1 (PPS-Mega): official announcement | Mega Prime
329·23518451+1 (PPS-Mega): official announcement | Mega Prime
323·23482789+1 (PPS-Mega): official announcement | Mega Prime
189·23596375+1 (PPS-Mega): official announcement | Mega Prime
387·23322763+1 (PPS-Mega): official announcement | Mega Prime
275·23585539+1 (PPS-Mega): official announcement | Mega Prime
251·23574535+1 (PPS-Mega): official announcement | Mega Prime
191·23548117+1 (PPS-Mega): official announcement | Mega Prime
141·23529287+1 (PPS-Mega): official announcement | Mega Prime
135·23518338+1 (PPS-Mega): official announcement | Mega Prime
249·23486411+1 (PPS-Mega): official announcement | Mega Prime
195·23486379+1 (PPS-Mega): official announcement | Mega Prime
197·23477399+1 (PPS-Mega): official announcement | Mega Prime
255·23395661+1 (PPS-Mega): official announcement | Mega Prime
179·23371145+1 (PPS-Mega): official announcement | Mega Prime
193·23329782+1 (PPS-Mega): official announcement | Fermat Divisor
129·23328805+1 (PPS-Mega): official announcement | Mega Prime

7·25775996+1 (PPS): official announcement | Mega Prime
9·23497442+1 (PPS): official announcement | Mega Prime
57·22747499+1 (PPS): official announcement | Fermat Divisor
267·22662090+1 (PPS): official announcement | Fermat Divisor
9·22543551+1 (PPS): official announcement | Fermat Divisor
25·22141884+1 (PPS): official announcement | Fermat Divisor
183·21747660+1 (PPS): official announcement | Fermat Divisor
131·21494099+1 (PPS): official announcement | Fermat Divisor
329·21246017+1 (PPS): official announcement | Fermat Divisor
2145·21099064+1 (PPS): official announcement | Fermat Divisor
1705·2906110+1 (PPS): official announcement | Fermat Divisor
659·2617815+1 (PPS): official announcement | Fermat Divisor
519·2567235+1 (PPS): official announcement | Fermat Divisor
651·2476632+1 (PPS): official announcement | Fermat Divisor
7905·2352281+1 (PPS): official announcement | Fermat Divisor
4479·2226618+1 (PPS): official announcement | Fermat Divisor
3771·2221676+1 (PPS): official announcement | Fermat Divisor
7333·2138560+1 (PPS): official announcement | Fermat Divisor

168451·219375200+1 (PSP): official announcement | k=168451 eliminated

10223·231172165+1 (SoB): official announcement | k=10223 eliminated

2996863034895·21290000±1 (SGS): official announcement | Twin
2618163402417·21290000-1 (SGS), 2618163402417·21290001-1 (2p+1): official announcement | SGS
18543637900515·2666667-1 (SGS), 18543637900515·2666668-1 (2p+1): official announcement | SGS
3756801695685·2666669±1 (SGS): official announcement | Twin

322498·52800819-1 (SR5): official announcement | k=322498 eliminated
88444·52799269-1 (SR5): official announcement | k=88444 eliminated
138514·52771922+1 (SR5): official announcement | k=138514 eliminated
194368·52638045-1 (SR5): official announcement | k=194368 eliminated
66916·52628609-1 (SR5): official announcement | k=66916 eliminated
81556·52539960+1 (SR5): official announcement | k=81556 eliminated
327926·52542838-1 (SR5): official announcement | k=327926 eliminated
301562·52408646-1 (SR5): official announcement | k=301562 eliminated
171362·52400996-1 (SR5): official announcement | k=171362 eliminated
180062·52249192-1 (SR5): official announcement | k=180062 eliminated
53546·52216664-1 (SR5): official announcement | k=53546 eliminated
296024·52185270-1 (SR5): official announcement | k=296024 eliminated
92158·52145024+1 (SR5): official announcement | k=92158 eliminated
77072·52139921+1 (SR5): official announcement | k=77072 eliminated
306398·52112410-1 (SR5): official announcement | k=306398 eliminated
154222·52091432+1 (SR5): official announcement | k=154222 eliminated
100186·52079747-1 (SR5): official announcement | k=100186 eliminated
144052·52018290+1 (SR5): official announcement | k=144052 eliminated
109208·51816285+1 (SR5): official announcement | k=109208 eliminated
325918·51803339+1 (SR5): official announcement | k=325918 eliminated
133778·51785689+1 (SR5): official announcement | k=133778 eliminated
24032·51768249+1 (SR5): official announcement | k=24032 eliminated
138172·51714207-1 (SR5): official announcement | k=138172 eliminated
22478·51675150-1 (SR5): official announcement | k=22478 eliminated
326834·51634978-1 (SR5): official announcement | k=326834 eliminated
207394·51612573-1 (SR5): official announcement | k=207394 eliminated
104944·51610735-1 (SR5): official announcement | k=104944 eliminated
330286·51584399-1 (SR5): official announcement | k=330286 eliminated
22934·51536762-1 (SR5): official announcement | k=22934 eliminated
178658·51525224-1 (SR5): official announcement | k=178658 eliminated
59912·51500861+1 (SR5): official announcement | k=59912 eliminated
37292·51487989+1 (SR5): official announcement | k=37292 eliminated
173198·51457792-1 (SR5): official announcement | k=173198 eliminated

273809·28932416-1 (TRP): official announcement | k=273809 eliminated
502573·27181987-1 (TRP): official announcement | k=502573 eliminated
402539·27173024-1 (TRP): official announcement | k=402539 eliminated
40597·26808509-1 (TRP): official announcement | k=40597 eliminated
304207·26643565-1 (TRP): official announcement | k=304207 eliminated
398023·26418059-1 (TRP): official announcement | k=398023 eliminated
252191·25497878-1 (TRP): official announcement | k=252191 eliminated
353159·24331116-1 (TRP): official announcement | k=353159 eliminated
141941·24299438-1 (TRP): official announcement | k=141941 eliminated
415267·23771929-1 (TRP): official announcement | k=415267 eliminated
123547·23804809-1 (TRP): official announcement | k=123547 eliminated
65531·23629342-1 (TRP): official announcement | k=65531 eliminated
428639·23506452-1 (TRP): official announcement | k=428639 eliminated
191249·23417696-1 (TRP): official announcement | k=191249 eliminated
162941·2993718-1 (TRP): official announcement | k=162941 eliminated

65516468355·2333333±1 (TPS): official announcement | Twin

17016602·217016602-1 (WOO): official announcement | Woodall
3752948·23752948-1 (WOO): official announcement | Woodall
2367906·22367906-1 (WOO): official announcement | Woodall
2013992·22013992-1 (WOO): official announcement | Woodall

## News

Be careful with BOINC computers on the Internet
A lot of us use Cloud servers such as AWS, or make our home computers or our computers at work accessible on the Internet so we can control their BOINC clients remotely.

I was looking through the logs of some Azure servers I have running BOINC, and saw this on one of them:

10316 8/7/2019 11:39:23 AM GUI RPC request from non-allowed address 2.0.25.129 10648 8/7/2019 1:09:27 PM GUI RPC request from non-allowed address 2.0.42.193 10649 8/7/2019 1:09:27 PM 256 connections rejected in last 10 minutes

In fact, a similar address (somewhere in France, supposedly) tried to connect to the BOINC client on four of my BOINC machines. This has been happening since at least July.

If the BOINC client on your computers is accessible from the Internet, I advise putting your specific IP address (or addresses) into remote_hosts.cfg rather than leaving it open to the world, or doing the same in a firewall (or both). And use a strong password.

If you don't think this is important... anyone who successfully connects to the BOINC client on your computer can attach it to their own BOINC server, which can then send it tasks that can easily install malicious payloads such as key loggers, spam relays, DDOS bots, and other bad stuff.

EDIT: If this is all Greek to you and you don't know what I'm talking about, you're probably not at risk. BOINC starts off with remote access disabled. You have to explicitly go and change configuration files to enable remote access, and probably modify your firewall as well. If you haven't done that, you're okay. 7 Aug 2019 | 20:41:03 UTC · Comment

GFN-524288 Mega Prime!
On 29 June 2019, 00:54:18 UTC, PrimeGrid’s Generalized Fermat Prime Search found the Generalized Fermat mega prime:

2877652^524288+1

The prime is 3,386,397 digits long and enters Chris Caldwell's The Largest Known Primes Database ranked 3rd for Generalized Fermat primes and 26th overall.

The discovery was made by Roman Vogt (Tabaluga) of Germany using an NVIDIA GeForce GTX 1060 in an Intel(R) Core(TM) i7-2700K CPU @ 3.50GHz CPU with 16GB RAM, running Windows 10. This GPU took about 1 hour and 42 minutes to probable prime (PRP) test with GeneferOCL5. Roman is a member of the Sicituradastra. team.

The PRP was verified on 29 June 2019, 08:52:47 by Carlo Villa (carlo) using an NVIDIA GeForce 830M in an Intel(R) Core(TM) i5-5200U CPU @ 2.20GHz with 8GB RAM, running Windows 10. This GPU took about 16 hours and 55 minutes to probable prime (PRP) test with GeneferOCL5.

The PRP was confirmed prime by an Intel(R) Xeon(R) CPU E3-1240 v6 @ 3.70GHz with 4GB RAM, running Linux. This computer took about 25 hours 53 minutes to complete the primality test using multithreaded LLR.

For more details, please see the official announcement.
8 Jul 2019 | 12:20:47 UTC · Comment

Another New SR5 Mega Prime!
On 23 June 2019, 14:39:48 UTC, PrimeGrid’s Sierpiński/Riesel Base 5 Problem project eliminated k=322498 by finding the mega prime:

322498*5^2800819-1

The prime is 1,957,694 digits long and enters Chris Caldwell's “The Largest Known Primes Database” ranked 63rd overall and is the largest known base 5 prime. 67 k’s now remain in the Riesel Base 5 problem.

The discovery was made by Jordan Romaidis of the United States using an Intel(R) Xeon(R) Gold 5120 CPU @ 2.20GHz with 96GB RAM running Microsoft Windows 10 Enterprise x64 Edition. This computer took 25 hours and 28 minutes to complete the primality test using multithreaded LLR. Jordan is a member of the San Francisco team.

The prime was verified on 24 June 2019, 20:59:33 UTC by Scott Brown of the United States using an AMD FX(tm)-8350 Eight-Core Processor with 16GB RAM running Microsoft Windows 10 Core x64 Edition. This computer took about 53 hours and 51 minutes to complete the primality test using multithreaded LLR. Scott is a member of the Aggie The Pew team.

For more details, please see the official announcement.
28 Jun 2019 | 20:11:13 UTC · Comment

New SR5 Mega Prime!
On 21 June 2019, 01:30:42 UTC, PrimeGrid’s Sierpiński/Riesel Base 5 Problem project eliminated k=88444 by finding the mega prime:

88444*5^2799269-1

The prime is 1,956,611 digits long and enters Chris Caldwell's “The Largest Known Primes Database” ranked 63rd overall and is the largest known base 5 prime. 68 k’s now remain in the Riesel Base 5 problem.

The discovery was made by Scott Brown of the United States using an Intel(R) Core(TM) i7-8700 CPU @ 3.20GHz with 32GB RAM running Microsoft Windows 10 Professional x64 Edition. This computer took 5 hours and 29 minutes to complete the primality test using multithreaded LLR. Scott is a member of the Aggie The Pew team.

The prime was verified on 21 June 2019, 14:50:01 UTC by Dave Sunderland (DaveSun) using an Intel(R) Core(TM) i7-6700HQ CPU @ 2.60GHz with 16GB RAM running Microsoft Windows 10 Core x64 Edition. This computer took about 12 hours and 32 minutes to complete the primality test using multithreaded LLR.

For more details, please see the official announcement.
28 Jun 2019 | 19:55:53 UTC · Comment

AVX-512 Now Supported by LLR
All of PrimeGrid's LLR applications now support AVX-512 on CPUs with that capability. Those of you that have been using app_info.xml/anonymous platform to run LLR 3.8.23 may now use the stock app if you wish, which is also LLR 3.8.23.

UPDATE May 22nd: It has come to my attention that while CPUs with 2 AVX-512 execution units gain a substantial boost in performance, mid-range CPUs with only 1 AVX-512 execution unit may see a significant decrease in performance with the new LLR app. Obviously, this is not intended. For the time being there is no workaround for this. If you have a CPU that supports AVX-512, but has only a single AVX-512 execution unit, you may want to use the anonymous platform mechanism (app_info.xml) to run the older version of LLR. With a challenge starting tomorrow, we won't make changes to the app until at least a week. We apologize for any inconvenience this may cause.

UPDATE May 23rd: I've included a list of single and dual unit AVX-512 CPUs here.
22 May 2019 | 0:22:04 UTC · Comment

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### Newly reported primes

(Mega-primes are in bold.)

2765*2^1544271+1 (Randall J. Scalise); 137148446^32768+1 (Brian R Kaczala); 137119120^32768+1 (Darryl); 65357568^65536+1 (Nick); 4596379921527*2^1290000-1 (Lobsterstew); 7205*2^1544267+1 (Tern); 137081730^32768+1 (RickyAwesome); 137081180^32768+1 (Darryl); 4596963138915*2^1290000-1 (Nita); 137018148^32768+1 (Kellen); 137006170^32768+1 (o-ando); 136972034^32768+1 (Kellen); 136951538^32768+1 (RickyAwesome); 2829*2^3323341+1 (4bc3); 136886522^32768+1 (Darryl); 136888478^32768+1 (Philipp Schulz); 4593987354495*2^1290000-1 (Andy); 4335*2^3323323+1 (288larsson); 1885*2^1544144+1 (CGB); 65217852^65536+1 (Charles Jackson)

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