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Message boards : News : World Record Generalized Cullen Prime!

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Van ZimmermanProject donor
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Discovered the World's First GFN-20 prime!!!Discovered 2 mega primesFound 1 prime in the 2018 Tour de Primes321 LLR Sapphire: Earned 20,000,000 credits (20,089,185)Cullen LLR Jade: Earned 10,000,000 credits (13,919,625)ESP LLR Sapphire: Earned 20,000,000 credits (20,082,497)Generalized Cullen/Woodall LLR Sapphire: Earned 20,000,000 credits (20,037,992)PPS LLR Sapphire: Earned 20,000,000 credits (20,106,782)PSP LLR Sapphire: Earned 20,000,000 credits (20,117,197)SoB LLR Sapphire: Earned 20,000,000 credits (21,208,789)SR5 LLR Jade: Earned 10,000,000 credits (14,389,640)SGS LLR Jade: Earned 10,000,000 credits (13,070,563)TRP LLR Sapphire: Earned 20,000,000 credits (20,619,871)Woodall LLR Jade: Earned 10,000,000 credits (15,165,651)Generalized Cullen/Woodall Sieve Sapphire: Earned 20,000,000 credits (20,199,057)PPS Sieve Double Amethyst: Earned 1,000,000,000 credits (1,051,222,753)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Jade: Earned 10,000,000 credits (10,189,695)TRP Sieve (suspended) Jade: Earned 10,000,000 credits (10,102,079)AP 26/27 Emerald: Earned 50,000,000 credits (51,669,540)GFN Double Ruby: Earned 2,000,000,000 credits (3,213,951,626)PSA Double Bronze: Earned 100,000,000 credits (185,178,671)
Message 113605 - Posted: 20 Jan 2018 | 13:01:34 UTC
Last modified: 20 Jan 2018 | 16:37:36 UTC

On 18 January 2018, 19:39:18 UTC, PrimeGrid’s Generalized Cullen/Woodall Prime Search found the largest known Generalized Cullen prime:

1323365*116^1323365+1

Generalized Cullen numbers are of the form: n*b^n+1. Generalized Cullen numbers that are prime are called Generalized Cullen primes. For more information, please see “Cullen prime” in The Prime Glossary (http://primes.utm.edu/glossary/xpage/Cullens.html).

The prime is 2,732,038 digits long and enters Chris Caldwell's The Largest Known Primes Database ranked 1st for Generalized Cullen primes and 30th overall.

Base 116 was one of 13 prime-less Generalized Cullen bases below b=121 that PrimeGrid is searching. The remaining bases are 13, 25, 29, 41, 47, 49, 55, 69, 73, 101, 109 & 121.

The discovery was made by Scott Brown (Scott Brown) of the United States using an Intel(R) Core(TM) i7-4770S CPU @ 3.10GHz with 4GB RAM, running Windows 10 Enterprise Edition. This computer took about 8 hours and 34 minutes to complete the primality test using multithreaded LLR. Scott is a member of the Aggie The Pew team.

The prime was verified on 19 January 2018 17:24:17 UTC by Serge De Saffel (lentosy) of Belgium using an Intel(R) Core(TM) i5-6600K CPU @ 3.50GHz with 16GB RAM, running Windows 10 Education Edition. This computer took about 15 hours 22 minutes to complete the primality test using LLR. Serge is a member of the team Sicituradastra.

For more details, please see the official announcement.

JeppeSNProject donor
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321 LLR Bronze: Earned 10,000 credits (48,835)ESP LLR Bronze: Earned 10,000 credits (13,226)PPS LLR Silver: Earned 100,000 credits (326,810)SoB LLR Silver: Earned 100,000 credits (132,293)TRP LLR Bronze: Earned 10,000 credits (14,746)PSA Turquoise: Earned 5,000,000 credits (7,614,290)
Message 116109 - Posted: 17 Mar 2018 | 16:12:44 UTC - in response to Message 113605.

Base 116 was one of 13 prime-less Generalized Cullen bases below b=121 that PrimeGrid is searching. The remaining bases are 13, 25, 29, 41, 47, 49, 55, 69, 73, 101, 109 & 121.
That was the only even base under 121 remaining. (Noticed this today when it was announced that base 41 has also been eliminated.) /JeppeSN

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Message boards : News : World Record Generalized Cullen Prime!

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