S/R Base 5 Primes reported in 2017+
Congratulations to Frank Schwegler for finding the 1st SR5 prime of 2017.
The prime 171362*5^24009961 found on 25 August 2017 eliminates k=171362 from the base 5 Riesel problem. The prime is 1,678,230 digits long and entered Chris Caldwell's “The Largest Known Primes Database” ([URL]http://primes.utm.edu/primes[/URL]) ranked 57th overall. 73 k's then remained in the Riesel Base 5 Problem. Congratulations to Håkan Lind for finding the 2nd SR5 prime of 2017. The prime 301562*5^24086461 found on 17 September 2017 eliminates k=301562 from the base 5 Riesel problem. The prime is 1,683,577 digits long and entered Chris Caldwell's “The Largest Known Primes Database” ([URL]http://primes.utm.edu/primes[/URL]) ranked 57th overall. 72 k's now remain in the Riesel Base 5 Problem. The base 5 Sierpinski problem has 33 k's remaining. Primegrid is currently running a 5 day challenge on the Sierpinski / Riesel Base 5 (SR5) project, ends 19th June 2018 00:00 UTC. For details, please read the post in the PrimeGrid forum: [URL]http://www.primegrid.com/forum_thread.php?id=8027[/URL] 
And new prime in this class is fall!

And another one :)
After long time two primes in difference of few days. 
S/R Base 5 Primes reported in 2018
Congratulations to Selya Tsuji for finding the 1st SR5 prime of 2018.
The prime 327926*5^25428381 found on 19 June 2018 eliminates k=327926 from the base 5 Riesel problem. The prime is 1,777,374 digits long and entered Chris Caldwell's “The Largest Known Primes Database” ([URL]http://primes.utm.edu/primes[/URL]) ranked 60th overall. 71 k's now remain in the Riesel Base 5 Problem. Congratulations to Jiří Bočan for finding the 2nd SR5 prime of 2018. The prime 81556*5^2539960+1 found on 20 June 2018 eliminates k=81556 from the base 5 Sierpinski problem. The prime is 1,775,361 digits long and entered Chris Caldwell's “The Largest Known Primes Database” ([URL]http://primes.utm.edu/primes[/URL]) ranked 61st overall. 32 k's now remain in the Sierpinski Base 5 Problem. Both of these primes were found just after the Primegrid SR5 challenge. 
To be pedantic, both workunits were sent out [i]during[/i] the challenge :)

S/R Base 5 Primes reported in 2018
Congratulations to Honza Cholt for finding the 3rd SR5 prime of 2018.
The prime 66916*5^26286091 found on 29 July 2018 eliminates k=66916 from the base 5 Riesel problem. The prime is 1,837,324 digits long and entered Chris Caldwell's “The Largest Known Primes Database” ([URL]http://primes.utm.edu/primes[/URL]) ranked 59th overall. 70 k's now remain in the Riesel Base 5 Problem. 
S/R Base 5 Prime reported in 2018
Congratulations again to Honza Cholt for finding the 4th SR5 prime of 2018.
The prime 194368*5^26380451 found on 15 August 2018 eliminates k=194368 from the base 5 Riesel problem. The prime is 1,843,920 digits long and entered Chris Caldwell's “The Largest Known Primes Database” ([URL]http://primes.utm.edu/primes[/URL]) ranked 60th overall. 69 k's now remain in the Riesel Base 5 Problem. 
And we have new SR5 prime!
[B][URL="http://primes.utm.edu/primes/page.php?id=126425"]138514*5^2771922+1[/URL][/B] found by Ken Ito on 26 April 2019 1937496 digits, position 63 
[QUOTE=pepi37;514878]And we have new SR5 prime!
[B][URL="http://primes.utm.edu/primes/page.php?id=126425"]138514*5^2771922+1[/URL][/B] found by Ken Ito on 26 April 2019 1937496 digits, position 63[/QUOTE] Wow! I'm the doublechecker for this prime on Primegrid. :cool: 
[QUOTE=unconnected;514899]Wow! I'm the doublechecker for this prime on Primegrid. :cool:[/QUOTE]
Use t option and be faster next time! 
And new one is arrived :)
[URL]https://primes.utm.edu/primes/page.php?id=126564[/URL] 88444 · 5^2799269  1 
[URL]https://primes.utm.edu/primes/page.php?id=126564[/URL]
88444 · 5[SUP]2799269[/SUP]  1 1956611 digits Jun 2019 It is the largest SR5 prime and the third largest prime of 2019 it eliminates k=88444 from the base 5 Reisel Problem. 
And another hit :)
[url]https://primes.utm.edu/primes/page.php?id=126585[/url] 322498 · 52800819  1 is prime :) 
[QUOTE=pepi37;520028]
322498 · 52800819 (sic)  1 is prime :)[/QUOTE] That is divisible by 7 :razz: 
Pepi,
Please use the exponentiation symbol. Thanks. 
[QUOTE=gd_barnes;520164]Pepi,
Please use the exponentiation symbol. Thanks.[/QUOTE] I never fail to do that, 
And new hit in SR5... prime will be verified soon :)
[url]https://primes.utm.edu/primes/page.php?id=130732[/url] 
Apparently there is another one?
[url]https://primes.utm.edu/primes/page.php?id=130751[/url] 146264*5^29532821 
And the third one of this month: 238694*5^2979422  1
[url]https://primes.utm.edu/primes/page.php?id=130771[/url] /JeppeSN 
Fourth one, 207494*5^3017502  1.
[url]https://primes.utm.edu/primes/page.php?id=130783[/url] /JeppeSN 
Seems this was not reported here yet:
[url='https://primes.utm.edu/primes/page.php?id=130869']118568 * 5^3112069+1[/url] is prime, found on 20200501 
[COLOR="Red"]Moderators: I am not too sure if this is the right (or best) thread to post this but please move it if required.[/COLOR]
A new Sierpinski/Riesel Base 5 has been found (verification pending) #23 in the list currently 3622 · 5[SUP]7558139[/SUP]  1 5282917 Digits L4965 (Ryan Propper) Feb 2022 This eliminates the smallest k in the list =3622 Riesel base 5 Congratulations to Ryan Propper. 
Congratulations Dr. Ryan.

One down for the Rieselbase 5 conjecture:
[url='https://primes.utm.edu/primes/page.php?id=134054']64598 * 5^37698541[/url] is prime, 2,635,020 digits, found on 20220614 by PrimeGrid. Curious: the 5 digits of the kvalue appear also in the nvalue. Awaiting official announcement, still some tasks open for this k. 
[QUOTE=kar_bon;607981]One down for the Rieselbase 5 conjecture:
[url='https://primes.utm.edu/primes/page.php?id=134054']64598 * 5^37698541[/url] is prime, 2,635,020 digits, found on 20220614 by PrimeGrid. Curious: the 5 digits of the kvalue appear also in the nvalue. Awaiting official announcement, still some tasks open for this k.[/QUOTE] Congratulations! This is the 97th prime with between 2 million and 3 million digits. There are 10 primes in total (in that range) of the form k* 5^n +/ 1. (8 with 1 and 2 with +1) 
[QUOTE=kar_bon;607981]One down for the Rieselbase 5 conjecture:
[URL="https://primes.utm.edu/primes/page.php?id=134054"]64598 * 5^37698541[/URL] is prime, 2,635,020 digits, found on 20220614 by PrimeGrid. Curious: the 5 digits of the kvalue appear also in the nvalue. Awaiting official announcement, still some tasks open for this k.[/QUOTE] Even more curious: The digits 3 through 9 all occur 1 time in the nvalue. 
And there is new one :)
[URL]https://primes.utm.edu/primes/page.php?id=134068[/URL] 63838 *5^38878511 2717497 digits, current 99 rank 
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