Some new Generalized Cullen and Woodall primes

Batalov · 2019-09-02, 17:43

(off-topic) It looks like PrimeGrid found either a Cullen or a Woodall.
We will likely see it posted in a couple days.

The n is apparently going to be even (in n*bⁿ +/- 1, and n >> 17,000,000, so -- more than a 5 million digiter).
Super!

P.S. Well, this is a generalized Cullen ...slightly less exciting - but still very cool.

paulunderwood · 2019-09-02, 18:04

Quote:

Originally Posted by Batalov

(off-topic) It looks like PrimeGrid found either a Cullen or a Woodall.
We will likely see it posted in a couple days.

The n is apparently going to be even (in n*bⁿ +/- 1, and n >> 17,000,000, so -- more than a 5 million digiter).
Super!

I am looking forward to their publication of their new top 20 prime.

paulunderwood · 2019-09-03, 06:49

It is actually 3,921,539 digits (rank 21) and is being tested at UTM now. The newly discovered prime is 2805222*25^2805222+1

Serge played a part in this by noting that n*b^n+-1 can be tested quicker by testing n*(sqrt(b))^(2*n)+-1, by over 10% when using the LLR program.

rudy235 · 2019-09-04, 00:40

Quote:

Originally Posted by paulunderwood

It is actually 3,921,539 digits (rank 21) and is being tested at UTM now. The newly discovered prime is 2805222*25^2805222+1

Serge played a part in this by noting that n*b^n+-1 can be tested quicker by testing n*(sqrt(b))^(2*n)+-1, by over 10% 0when using the LLR program.

Once verified (as far as UTM goes) it will be the largest prime discovered this year 2019.

It becomes the largest Generalized Cullen superseding the one discovered last year in March that had 2,913,785 digits.

http://www.primegrid.com/download/gc41-1806676.pdf

LaurV · 2019-09-04, 15:56

Yeaaa on the way to 100M digits! Any long way starts with a small step...
Congrats!

Batalov · 2019-09-05, 04:44

{blowhard mode on}

My GW is still top 1! :-)

{blowhard mode off /}

rudy235 · 2019-09-11, 21:09

Quote:

Originally Posted by rudy235

Once verified (as far as UTM goes) it will be the largest prime discovered this year 2019.

It becomes the largest Generalized Cullen superseding the one discovered last year in March that had 2,913,785 digits.

http://www.primegrid.com/download/gc41-1806676.pdf

Finally, we have the official announcement ready.

http://www.primegrid.com/download/gc25-2805222.pdf

Batalov · 2019-09-17, 12:33

A generalized Woodall is on its way, too. (and it is a near-quasi-repdigit, too.)

There could be a couple more in the bag - over a week or so.

paulunderwood · 2019-09-30, 21:26

Quote:

Originally Posted by Batalov

A generalized Woodall is on its way, too. (and it is a near-quasi-repdigit, too.)

There could be a couple more in the bag - over a week or so.

Congrats to you and Ryan for the 3,028,951 digit prime 874208 *2916^874208 - 1

paulunderwood · 2019-10-26, 19:55

Congrats ro Serge and Ryan for the 20th largest known prime: 2740879*32^2740879 - 1

rudy235 · 2019-10-27, 05:04

Quote:

Originally Posted by paulunderwood

Congrats ro Serge and Ryan for the 20th largest known prime: 2740879*32^2740879 - 1

It is the largest Generalized Woodall and with 4125441 digits it is the Third Prime with more than 4 million Digits (and < than 5M)
Congratulations to Ryan and Serge

2019-09-02, 17:43	#1
Batalov "Serge" Mar 2008 Phi(4,2^7658614+1)/2 10010000101001₂ Posts	Some new Generalized Cullen and Woodall primes (off-topic) It looks like PrimeGrid found either a Cullen or a Woodall. We will likely see it posted in a couple days. The n is apparently going to be even (in nbⁿ +/- 1, and n >> 17,000,000, so -- more than a 5 million digiter). Super! P.S. Well, this is a generalized Cullen* ...slightly less exciting - but still very cool.

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2019-09-03, 06:49	#3
paulunderwood Sep 2002 Database er0rr 3,527 Posts	It is actually 3,921,539 digits (rank 21) and is being tested at UTM now. The newly discovered prime is 280522225^2805222+1 Serge played a part in this by noting that nb^n+-1 can be tested quicker by testing n(sqrt(b))^(2n)+-1, by over 10% when using the LLR program.

2019-09-04, 15:56	#5
LaurV Romulan Interpreter Jun 2011 Thailand 3·17·179 Posts	Yeaaa on the way to 100M digits! Any long way starts with a small step... Congrats!

2019-09-05, 04:44	#6
Batalov "Serge" Mar 2008 Phi(4,2^7658614+1)/2 10010000101001₂ Posts	{blowhard mode on} My GW is still top 1! :-) {blowhard mode off /}

2019-09-17, 12:33	#8
Batalov "Serge" Mar 2008 Phi(4,2^7658614+1)/2 2429₁₆ Posts	A generalized Woodall is on its way, too. (and it is a near-quasi-repdigit, too.) There could be a couple more in the bag - over a week or so.

2019-10-26, 19:55	#10
paulunderwood Sep 2002 Database er0rr 3,527 Posts	Congrats ro Serge and Ryan for the 20th largest known prime: 2740879*32^2740879 - 1