Other Primes

[Batalov]

Originally Posted by paulunderwood

Congrats to Roman Trunov and Brian D. Niegocki for the (GFN based) Cunningham Chain 893962950^16384+1 and 2*893962950^16384+1, at 146,659 digits smashing the previous record of 77,078 digits.

It was a nice idea, but not sure what (re-)sieve they used. Sure, they had a well-sieved (and dense) b^16384+1 set from past times, but 2*b^16384+1 (and/or b^16384/2+1, too) had to be sieved, which does not look too fast.

Easier to improve that with a traditional sieve, I would think...
213778324725*2^561417+1 (p)
213778324725*2^561418+1 (2p-1)

[paulunderwood]

Originally Posted by Batalov

It was a nice idea, but not sure what (re-)sieve they used. Sure, they had a well-sieved (and dense) b^16384+1 set from past times, but 2*b^16384+1 (and/or b^16384/2+1, too) had to be sieved, which does not look too fast.

Easier to improve that with a traditional sieve, I would think...
213778324725*2^561417+1 (p)
213778324725*2^561418+1 (2p-1)

Congrats for the 169,015 digits pair.

[Cybertronic]

Congrats, page was updated !
https://www.pzktupel.de/JensKruseAndersen/cc.php

[pepi37]

New 1.58M near-repdigit is found :)
From last hit in same sequence difference is only cca 8500 candidates :) ( and 2.5 years time difference) :)

And now it is official :)

https://t5k.org/primes/page.php?id=135919

92 ·10^1585996-1

[numberMX]

PrimeGrid has just found 3 * 2^20928756 - 1, 6,300,184 digits long.

[paulunderwood]

After a recent "drive" on crunching 321 candidates to celebrate Blaise Pascal's 400th birthday, Arno Lehmann has found the 19th largest prime to date: 3 *2^20928756-1 (6,300,184 digits).

[Cybertronic]

Congratulation to a new rexord Thabit-prime !!!