mersenneforum.org Generalized Cullen and Woodall Searches
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 2017-01-21, 11:55 #23 sweety439   Nov 2016 22·691 Posts What is the current search limit for generalized Cullen prime base 13 (n*13^n+1)?
2017-01-21, 14:13   #24
rogue

"Mark"
Apr 2003
Between here and the

31·199 Posts

Quote:
 Originally Posted by sweety439 What is the current search limit for generalized Cullen prime base 13 (n*13^n+1)?
1,000,000 per this.

2017-09-15, 20:54   #25
sweety439

Nov 2016

22·691 Posts

Quote:
 Originally Posted by rogue The difference is in the definition: The reason for the restriction on the exponent n is simple, without some restriction every prime p would be a generalized Woodall. so any prime that can be written in this form could be called a generalized Cullen prime This means that some p can be generalized Cullens, but all p can be generalized Woodalls.
However, we felt that the two sides should be consistent in their approach, in the definition of http://primes.utm.edu/glossary/xpage/Cullens.html and http://primes.utm.edu/glossary/xpage/WoodallNumber.html, no matter for the +1 (Cullen) side or for the -1 (Woodall) side, there is a condition that n >= b-1. However, for the sequence "numbers n such that n*b^n+-1 is prime", we can choose to allow n < b-1.

 2017-10-20, 06:15 #26 sweety439   Nov 2016 22·691 Posts Mersennewiki page for this project: http://www.mersennewiki.org/index.php/Cullen (Cullen) and http://www.mersennewiki.org/index.php/Woodall_numbers (Woodall).
 2019-11-14, 11:48 #27 sweety439   Nov 2016 22×691 Posts A prime is missing in http://guenter.loeh.name/gc/status.html: 1806676*41^1806676+1, also, a prime is missing in http://harvey563.tripod.com/GClist.txt: 177482 *117^177482 +1
 2019-11-14, 16:47 #28 Batalov     "Serge" Mar 2008 Phi(4,2^7658614+1)/2 47×197 Posts What makes you think that Loeh and Harvey read this forum? Hint: instead, just email them!
2019-11-14, 17:16   #29
rogue

"Mark"
Apr 2003
Between here and the

31×199 Posts

Quote:
 Originally Posted by Batalov What makes you think that Loeh and Harvey read this forum? Hint: instead, just email them!
I know that Steven has been on this forum in the past, but is probably isn't one of his usual haunts. If you point him to this thread, then he might visit more often.

2019-11-20, 14:01   #30
sweety439

Nov 2016

22·691 Posts

Quote:
 Originally Posted by Batalov What makes you think that Loeh and Harvey read this forum? Hint: instead, just email them!
I emailed them, but I only have Gmail, I see Loeh's email is "guenter@loeh.name", and Harvey's email is "harvey563@yahoo.com", neither is Gmail (I use Gmail to type these two email addresses ....

2020-11-10, 18:15   #31
bur

Aug 2020

3710 Posts

Does anyone know if the lists are still actively maintained? And is the search organized in any way? PG has a generalized C/W project, but it only covers bases up to 140 or so. Where did the others originate from?

Quote:
 Originally Posted by sweety439 I emailed them, but I only have Gmail, I see Loeh's email is "guenter@loeh.name", and Harvey's email is "harvey563@yahoo.com", neither is Gmail (I use Gmail to type these two email addresses ....
What does it matter if they use gmail? Fortunately e-mail is from the golden days of internet when protocols were open standards and any e-mail provider accepts mail from any other. Imagine instant messaging to be like that.

2020-11-10, 18:57   #32
rogue

"Mark"
Apr 2003
Between here and the

11000000110012 Posts

Quote:
 Originally Posted by bur Does anyone know if the lists are still actively maintained? And is the search organized in any way? PG has a generalized C/W project, but it only covers bases up to 140 or so. Where did the others originate from?
You have to reach out to them to see if they are still around and actively maintaining their websites.

The searches are only coordinated from the perspective the they track reservations and completed ranges from individuals that communicate with them. They do not set up servers (BOINC or PRPNet) for outsiders to access and participate.

PrimeGrid is only searching bases (to a limit) with no known prime because those bases are interesting.

You need to remember that people set up websites for searches like this because it interests them.

If Günter and Steven are no longer interested in hosting the pages, then someone else can take ownership and coordinate continued searching for GCW primes.

Steven's last post to this forum is at the same time of his last update to his website. I have no idea what his status is. I have no biographical information on him.

Günter is 76 (per his website) with no updates in nearly a year. I have no idea what his status is either.

 2020-11-10, 22:03 #33 kar_bon     Mar 2006 Germany 54628 Posts My Wiki got the possibility to create pages for (Near/Generalized) Cullen/Woodall search with reserving any base by a user. For now there're only a few pages done including history taken from those pages mentioned above. There're also pages for PG Gen.Cullen and PG Cullen searches, the Woodall page is not yet created but base 2 is reserved by PG, too. Any base can be created with own page using special templates for them.

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