Other Primes - Page 30

Batalov · 2023-03-17, 05:39

Quote:

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 · 2023-03-17, 07:37

Quote:

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 · 2023-03-17, 13:35

Congrats, page was updated !
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2023-03-17, 13:35	#322
Cybertronic Jan 2007 Germany 2⁴×41 Posts	Congrats, page was updated ! https://www.pzktupel.de/JensKruseAndersen/cc.php