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Message boards : News : Another World Record Generalized Cullen Prime!

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Van ZimmermanProject donor
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Joined: 30 Aug 12
Posts: 1850
ID: 168418
Credit: 4,856,794,517
RAC: 3,913,111
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 (15,394,422)ESP LLR Sapphire: Earned 20,000,000 credits (20,089,407)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 (16,162,333)SGS LLR Jade: Earned 10,000,000 credits (14,134,698)TRP LLR Sapphire: Earned 20,000,000 credits (20,619,871)Woodall LLR Jade: Earned 10,000,000 credits (16,756,395)Generalized Cullen/Woodall Sieve Sapphire: Earned 20,000,000 credits (20,322,471)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 (3,322,551,313)PSA Double Bronze: Earned 100,000,000 credits (186,711,974)
Message 116107 - Posted: 17 Mar 2018 | 15:44:44 UTC
Last modified: 17 Mar 2018 | 15:45:15 UTC

On 11 March 2018, 23:54:40 UTC, PrimeGrid’s Generalized Cullen/Woodall Prime Search found the largest known Generalized Cullen prime:

1806676*41^1806676+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.

The prime is 2,913,785 digits long and enters Chris Caldwell's The Largest Known Primes Database ranked 1st for Generalized Cullen primes and 27th overall.

Base 41 was one of 12 prime-less Generalized Cullen bases below b=121 that PrimeGrid is searching. The remaining bases are 13, 25, 29, 47, 49, 55, 69, 73, 101, 109 & 121.

The discovery was made by Hiroyuki Okazaki (zunewantan) of Japan using an Intel(R) Xeon(R) E5-2670 CPU @ 2.60GHz with 4GB RAM, running Linux. This computer took about 7 hours and 13 minutes to complete the primality test using multithreaded LLR. Hiroyuki is a member of the Aggie The Pew team.

The prime was verified on 12 March 2018 09:07:23 UTC by Scott Brown (Scott Brown) of the United States using an Intel(R) CPU @ 2.30GHz with 16GB RAM, running Windows 10 Professional Edition. This computer took about 15 hours 22 minutes to complete the primality test using LLR. Scott is also a member of the Aggie The Pew team.

For more details, please see the official announcement.

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ID: 69762
Credit: 16,618,249
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321 LLR Amethyst: Earned 1,000,000 credits (1,020,991)Cullen LLR Gold: Earned 500,000 credits (519,031)ESP LLR Gold: Earned 500,000 credits (718,571)Generalized Cullen/Woodall LLR Gold: Earned 500,000 credits (512,387)PPS LLR Amethyst: Earned 1,000,000 credits (1,490,681)PSP LLR Amethyst: Earned 1,000,000 credits (1,023,931)SoB LLR Amethyst: Earned 1,000,000 credits (1,159,647)SR5 LLR Amethyst: Earned 1,000,000 credits (1,014,311)SGS LLR Gold: Earned 500,000 credits (639,894)TRP LLR Gold: Earned 500,000 credits (510,413)Woodall LLR Gold: Earned 500,000 credits (528,909)Generalized Cullen/Woodall Sieve Ruby: Earned 2,000,000 credits (2,206,539)PPS Sieve Amethyst: Earned 1,000,000 credits (1,361,775)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Amethyst: Earned 1,000,000 credits (1,135,080)TRP Sieve (suspended) Amethyst: Earned 1,000,000 credits (1,119,667)AP 26/27 Gold: Earned 500,000 credits (517,504)GFN Gold: Earned 500,000 credits (501,037)PSA Gold: Earned 500,000 credits (637,882)
Message 116124 - Posted: 18 Mar 2018 | 4:35:13 UTC
Last modified: 18 Mar 2018 | 4:54:21 UTC

Recent significant primes column on the home page does not match the news column in regards to the number mentioned.

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Message boards : News : Another World Record Generalized Cullen Prime!

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