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Kosmaj 2006-09-21 22:28

Other Primes
 
I thought it would be nice to have a thread discussing primes found by others, or by us but not related to RPS.

And the first one is
2^1203793-2^601897+1 (362378 digits)

new [URL="http://primes.utm.edu/top20/page.php?id=41"]Gaussian Mersenne norm[/URL] record set by Cruelty. More details can be found [URL="http://www.mersenneforum.org/showthread.php?p=87695#post87621"]here[/URL]

Congratulations!

The form can be searched using the latest version of LLR (3.7.x). I tried once at 400k but it was a bit time consuming (on my laptop) and I gave up.

lsoule 2006-09-21 23:02

Earlier this month I found 99*10^139670-1, the new [URL="http://primes.utm.edu/top20/page.php?id=15"]Near-repdigit[/URL] record. In fact, 10 of the top 20 for this form have been entered in the last
2-3 months.

Kosmaj 2006-10-11 03:16

Badges marking the latest 9.8M-digit Mersenne prime are available in [URL="http://www.mersenneforum.org/showthread.php?t=6421"]this thread[/URL]. Sign up there if you'd like to have one.

Cruelty 2006-11-16 21:57

(2^1127239+2^563620+1)/5 is 3-PRP!, which AFAIK is the largest GQ so far :smile:
The question I have now is, how to prove it is, or it is not a prime :question:
BTW: I don't consider using PRIMO or other ECPP based software for this purpose as it would take more than my life to complete :rolleyes:

Kosmaj 2006-11-20 01:55

Replies to the above post moved to a separate thread:

[URL="http://www.mersenneforum.org/showthread.php?t=6657"]GQ(1127239) is PRP![/URL]

Please post further replies there.

Cruelty 2006-12-02 09:22

Check [URL="http://primes.utm.edu/primes/page.php?id=78939"]this[/URL] out :shock:

Kosmaj 2006-12-02 18:35

Yes, huge
26773*2^2465343-1, 742147 digits.

20th of all times!
Note that now an entry to Top-100 requires binary exponent n>1.2M !

robert44444uk 2007-01-17 11:39

Monster
 
Someone, outside of this group I think has posted a monster

[url]http://primes.utm.edu/primes/page.php?id=79192[/url]

21st largest prime every found!!!

Kosmaj 2007-01-17 12:44

That's L191, S. Banka who is (unfortunately :smile: ) not with us. He found 5 large primes in only one year, he began with 12121 project but now he is testing k=737 (=11*67) alone. He is now 13th by score!:surprised 4 of his 5 primes are currently in top-100, only Cooper and Heuer have more primes in top-100 while Grobstich has 4 too.

Thomas11 2007-01-17 12:57

[QUOTE=Kosmaj;96369]... while Grobstich has 4 too.[/QUOTE]

... and Thomas has 4 in the Top-101. :grin:

Kosmaj 2007-01-25 14:46

Congrats to David Underbakke (L99) who just reported new largest Sophie-Germain pair (51910 digits):
48047305725*2^172403-1
48047305725*2^172404-1

Only 10 days after the new twin record!

Kosmaj 2007-01-26 01:37

New record Woodall :surprised What a surprise! :shock:

[URL="http://primes.utm.edu/primes/page.php?id=79267"]1268979*2^1268979-1 [/URL] (382007 digits)

Discovered by W. Siemelink using LLR (L201). Congrats!

Cruelty 2007-02-14 22:02

Check [URL="http://primes.utm.edu/primes/page.php?id=79378"]this[/URL] out. [B]k>60bit[/B] found using [B]LLR[/B]

m_f_h 2007-03-15 17:40

I hope my post won't clutter up this thread too much ; my excuses in advance if so, and moderators, please move it to wherever it should be if this place is not OK !
I just discovered the existence of LLR.
Is the search for GM's somewhere somehow coordinated ?
(People declaring to search some ranges...)
To what extend are the gmfcandidates prefactored or elsehow selected ?
I just ran llr somehow randomly on such a candidate and it IMMEDIATELY (time << 1 second) found a factor (2^16666417-...+1 has factor 18068995989053)
- how comes that this easy finding is not mentioned in the gmfcand... file while other bigger factors are there ?
Again sorry for my ignorance and maybe inappropriate posting...
PS: the llr program does not seem to write a save file when it's killed, like mprime...?

Cruelty 2007-03-15 23:13

gmfcandidates is prefactored to 32 bits for both GM and GQ, meaning that only if a factor is found for both such an exponent has been eliminated... however by default LLR will look only for GMs so only GM factors will be reported. Check out LLR documentation for details.

BTW: when exiting LLR it will always save it's current progress.

Cruelty 2007-06-08 08:35

[URL="http://primes.utm.edu/primes/page.php?id=80955"]New Woodall record [/URL] :tu:

Siemelink 2007-06-08 09:43

[QUOTE=Cruelty;107914][URL="http://primes.utm.edu/primes/page.php?id=80955"]New Woodall record [/URL] :tu:[/QUOTE]

I am very happy. I've found now two Woodall primes in 10 months. Allthough the first two months I was unaware that they are called Woodall primes and that I wasn't the first to think of their special form n*2^n-1.

Willem.

Cruelty 2007-06-08 13:07

Congratulations!!!

Kosmaj 2007-06-27 06:39

Jeff (L399) of TPS dumped alone about 60 primes at n=333,333 yestreday :shock: One more such dump and he will be in top-10 by number! :w00t:

Kosmaj 2007-07-21 22:10

Congrats to Maks and his son on new largest repunit PRP:

(10^270343-1)/9

Cruelty 2007-08-04 20:31

3 Generalized Fermat primes have been reported under an anonymous account [URL="http://primes.utm.edu/primes/page.php?id=81870"]first[/URL], [URL="http://primes.utm.edu/primes/page.php?id=81869"]second[/URL], [URL="http://primes.utm.edu/primes/page.php?id=81868"]third[/URL] - congrats!

VBCurtis 2007-08-05 03:07

Those 3 are a pretty fortunate grouping! I'd ask "what are the chances?", but knowing this forum, someone would actually calculate it. :rolleyes:

Anyone know if primality testing generalized fermats is faster or slower than LLR for same-size riesel numbers?

-Curtis

Kosmaj 2007-08-05 04:04

It is really a pretty grouping, but GFs are very heavy weight, therefore I don't think it's unusual.

As for the speed, Proth.exe was specifically optimized for GF's. Maybe LLR is faster only for small k's. But Proth.exe has a limit on base [I]b[/I] (in b^2^k+1), for k=16 I think it's about 2M (so only b<2M can be tested).

As for the status of GF search, I think all values have been already extensively sieved and all them have been reserved but some people never completed their reserved ranges. Furthermore, about 2 years ago Yves Gallot who crated Proth.exe disappeared from the prime searching community, and since about that time GF projects began to lose popularity.

BTW, the account is not anonymous, it's written in the disclaimer that they were found by Dirk Schlueter who doesn't have an account on Top-5000. Most likely prof Caldwell found out about them through his private channels.

Kosmaj 2007-08-06 04:15

I just realized that Dirk's bases are at the 17M level, which means he didn't use Proth.exe, but most likely genefer80, another software written by Yves Gallot which can work with a base of any size. But it's much slower than Proth.exe because it is simulating 80-bit floating point precision in software. New 64-bit cpu's support 80-bit fp arithmetic nativelly but as I said Yves is not around to do the changes.

kar_bon 2007-08-09 20:24

new biggest Woodall prime
 
251749*2^2013995-1 is the new No.1 Woodall Prime (606279 digits)!

Cruelty 2007-08-14 21:37

[URL="http://primes.utm.edu/primes/page.php?id=81935"]Looks like "15k" is back[/URL].

lsoule 2007-08-15 04:58

With a k without a 3 or a 5 in it :grin:

Flatlander 2007-08-15 12:35

From his website:
"Currently we are focusing on fixed n candidates, which are faster than fixed k searches"

Cruelty 2007-09-03 07:55

Looks like [URL="http://primes.utm.edu/primes/page.php?id=82110"]another record Woodall[/URL] prime for Primegrid :tu:

Kosmaj 2007-09-03 10:06

Yes, amazing, the previous one also at the 2M level was found less than a month ago...

Kosmaj 2007-11-01 02:22

SOB striked again, with a huge prime

33661*2^7031232+1

with more than 2.1 M digits :shock: The 10th largest of all times. It's a result of their double-checking effort and thus smaller than their previous prime (at n=13M).

gd_barnes 2007-11-01 15:42

[quote=Kosmaj;117507]SOB striked again, with a huge prime

33661*2^7031232+1

with more than 2.1 M digits :shock: The 10th largest of all times. It's a result of their double-checking effort and thus smaller than their previous prime (at n=13M).[/quote]


Way to go seventeen-or-bust!! That makes a good case for double-checking I'd say! :smile:

Kosmaj 2007-11-07 12:38

3 Large GRUs
 
Congrats to Andy Steward on 3 new generalized rep-units in top-10! The largest one:
(13096^5953-1)/13095, 24506 digits

is currently second largest, about 1500 digits more than the GRU found by Larry and me 2 years ago (the world record at the time), which is now 3rd.

For each of his proven GRUs Andy provides a detailed commentary, so that with little self-study everybody can try to enter the field and find his first GRU. The commentary for the above prime can be found [URL="http://www.primes.viner-steward.org/andy/E/33281741.html"]here[/URL].

However, beware that entering Top-20 is not easy!

Kosmaj

Kosmaj 2007-11-09 02:30

Posts about k*10^n-1 moved to [URL="http://www.mersenneforum.org/showthread.php?t=9578"]another thread[/URL].

Please post new messages on this topic there.

gd_barnes 2007-12-14 21:18

New Conjectures 'R Us prime search effort
 
Hi all...

Come check out the new "Conjectures 'R Us" prime search effort [URL="http://www.mersenneforum.org/showthread.php?t=9738"]here[/URL]. There's plenty of bases and k's for everyone to search and have fun.


Gary

Cruelty 2007-12-26 19:13

Check [URL="http://primes.utm.edu/primes/page.php?id=83407"]this[/URL] out... if this is part of primegrid, then we will fall to #5 I guess... (in terms of score)

mdettweiler 2007-12-26 19:21

[quote=Cruelty;121569]Check [URL="http://primes.utm.edu/primes/page.php?id=83407"]this[/URL] out... if this is part of primegrid, then we will fall to #5 I guess... (in terms of score)[/quote]
I don't see PrimeGrid in the prover code...though I can't imagine why someone would be searching for Woodall primes outside of PrimeGrid (since they would be duplicating a lot of work, especially the sieving work). It's roughly in the range that PrimeGrid is searching, though, so I wouldn't be surprised if it was a PrimeGrid thing, just that the finder forgot to include PrimeGrid in his prover code. (I'm sure if that's the case, though, the Prime Pages people will fix it.)

Kosmaj 2007-12-26 21:46

Cruelty

We can sustain this one, still 4th, but not the next larger one.

Cruelty 2007-12-27 00:29

[QUOTE=Kosmaj;121588]We can sustain this one, still 4th, but not the next larger one.[/QUOTE]That is why we are all waiting for your k=7 prime :tu: + some other megabit primes are long overdue from me :wink:

Kosmaj 2008-01-17 00:31

Congrats to Richard (L185) on a huge prime
3139*2^3321905-1

only 3 digits shy of one million digits! He found the 9th SoB prime in 2005 (4847*2^3321063+1, 999744 digits) and is currently ranked 14th person by score.

Retep 2008-02-02 15:09

.
 
Prof. Cooper found another very large prime:
7 * 2^3015762+1 (907836 digits).

By the way, can I somewhere find an overview how fast the different forms of numbers can be tested at the moment (for a example a comparison of the forms k*2^n-1, k*2^n+1, k*b^n+/-1)?

Kosmaj 2008-02-03 14:03

Yes, that's his largest prime after two Mersennes.
We are now waiting to see is it a Fermat or a GF divisor, I'm sure he is now working on those tests.

As for the processing speed, when b=2, both -1 and +1 are about the same for the given k. When b>2 it's much slower (except, of course when b is a power of 2).

Cruelty 2008-03-08 23:32

1 Attachment(s)
4*3^311835-1 (148784 digits)
Attached is a list of primes for k=4 b=3.

Kosmaj 2008-03-10 04:55

[B]Cruelty[/B]

Congrats on a nice effort and a nice prime!

I remember that prof. Iskra had a special speed-up for
a^2*3^n+1, (n odd)

and found a number of large primes. I just found that [URL="http://www.ams.org/proc/2002-130-02/S0002-9939-01-06100-7/home.html"]his article[/URL] is now available free of charge! The Corollary 2.3 won't be difficult to implement uisng GMP...

Cruelty 2008-03-10 08:40

Thanks :smile:
I am testing both k=2 and k=4 using PRP v.24.14 currently @ n=315000.

Cruelty 2008-03-13 07:53

[URL="http://primes.utm.edu/primes/page.php?id=84401"]Another megaprime this year[/URL].

Kosmaj 2008-03-17 12:37

Yes, it's

24518^262144+1 (1150678 digits)

The new largest Generalized Fermat prime, found by Stephen Scott.
Currently ranked 13th.

Congrats!

Cruelty 2008-04-07 15:59

[URL="http://primes.utm.edu/primes/page.php?id=84603"]Looks like we won't defend our current position in terms of score[/URL] :shock:

Kosmaj 2008-04-07 20:45

It's huge, congrats to them!

But it's reported jointly by two projects and they will share
credit, so we won't be far behind.

BTW, I also wonder what kind of "project" PrimeGrid is? They have reported so far twin candidates, Woodalls, and now Prime Sierpinski. They are also working on 3*2^n-1, and I heard they would like to run Proth and some generalized Woodalls. Looks to me like a team, not any particular project...

mdettweiler 2008-04-07 21:27

[quote=Kosmaj;131046]It's huge, congrats to them!

But it's reported jointly by two projects and they will share
credit, so we won't be far behind.

BTW, I also wonder what kind of "project" PrimeGrid is? They have reported so far twin candidates, Woodalls, and now Prime Sierpinski. They are also working on 3*2^n-1, and I heard they would like to run Proth and some generalized Woodalls. Looks to me like a team, not any particular project...[/quote]
They have lots of different "subprojects", many of which are actually just BOINC faces on existing mersenneforum prime-search projects. Each user can choose in his preferences what mix of subprojects he'd like to be assigned work from. :smile:

Kosmaj 2008-04-07 21:42

I meant "project" on Top-5000 rankings. Each project there is supposed to be about a particular subset of all prime types, not primes of all types.

mdettweiler 2008-04-07 21:44

[quote=Kosmaj;131051]I meant "project" on Top-5000 rankings. Each project there is supposed to be about a particular subset of all prime types, not primes of all types.[/quote]
Oh, I see.

Cruelty 2008-04-17 07:44

Here goes another [URL="http://primes.utm.edu/bios/code.php?code=L606"]megaprime[/URL] Congratulations!

Kosmaj 2008-05-02 08:03

Congrats to RieselSieve on their latest prime
113983*2^3201175-1

with almost a million digits!

They are now 4th by score and we are 5th.
[CODE]
3 PrimeGrid 12.5 48.1833
4 Riesel Sieve Project 30 48.1155
5 Riesel Prime Search 616 47.9569
[/CODE]

Cruelty 2008-05-23 22:07

Another k=4, b=3 prime
 
4*3^350767-1 (167359 digits)

em99010pepe 2008-05-24 12:27

[quote=Cruelty;134167]4*3^350767-1 (167359 digits)[/quote]

You stall the server for 13.86 hours!!! lol
Congratulations.

Cruelty 2008-05-24 14:00

Verification took me 32200 seconds on a 3GHz Core2 :smile:

Cruelty 2008-05-30 05:28

Another k=4, b=3 prime
 
4*3^353635-1 (168728 digits)

Kosmaj 2008-05-30 06:01

Congrats on yet another one, very close to the one you reported a week ago.
:shock::smile:

Cruelty 2008-05-30 12:21

Thanks! It's time for k=2 prime :wink:

em99010pepe 2008-06-01 18:45

Benson prime:

[url=http://primes.utm.edu/primes/page.php?id=85095]19*2^1684813-1[/url]

Cruelty 2008-06-10 09:05

[URL="http://primes.utm.edu/primes/page.php?id=85126"]Another one from Curtis Cooper[/URL] :tu:

Flatlander 2008-06-10 23:10

Twin Prime
 
108615*2^110342+-1 is twin prime!

Comes in at 7th place :smile:

Kosmaj 2008-06-13 01:09

Congrats on a nice twin!

If it's not a secret how many n's did you check? I suppose you used the approach recently suggested by Robert Smith (?) Or, how many LLR tests in total?

Thanks.

Flatlander 2008-06-13 16:11

[quote=Kosmaj;135790]Congrats on a nice twin!

If it's not a secret how many n's did you check? I suppose you used the approach recently suggested by Robert Smith (?) Or, how many LLR tests in total?

Thanks.[/quote]
Thanks Kosmaj.
Well, I'm not sure how much to give away because I intend to search higher and I don't know how much was pure luck and how much was technique.
I suspect a large amount of luck because it was found after just 220,000 candidates and 164 Riesel primes. (Just 10 days on all 4 cores at 3.18GHz, including sieving.)
It's a refinement of this idea:
[URL]http://mersenneforum.org/showpost.php?p=117068&postcount=6[/URL]

I'm now searching for the No.1 twin until I find one or get bored. Probably the latter.

Chris

Kosmaj 2008-06-30 01:44

A new k=27 prime by 12121:
27*2^1253870-1 (377454 digits)

Congrats to Frank (L65)!

MooooMoo 2008-07-21 19:09

This is a bit old, but Rieselsieve found a million+ digit prime a month ago:

[url]http://primes.utm.edu/primes/page.php?id=85221[/url]

Unfortunately, their website, [url]http://www.rieselsieve.com/[/url] , appears to have been down for the past two weeks.

kar_bon 2008-07-22 13:36

[QUOTE=MooooMoo;138119]This is a bit old, but Rieselsieve found a million+ digit prime a month ago:

[url]http://primes.utm.edu/primes/page.php?id=85221[/url]

Unfortunately, their website, [url]http://www.rieselsieve.com/[/url] , appears to have been down for the past two weeks.[/QUOTE]

yes, i noticed this prime first in the Top-5000 database.

see [url]http://www.rieselprime.org/RieselProblem.htm[/url] too

Cruelty 2008-07-28 14:51

[URL="http://primes.utm.edu/primes/page.php?id=85350"]WOW![/URL] :tu:

Cruelty 2008-08-18 14:15

According to PrimeGrid news they have found a new "321" prime. This will most likely put RPS on the 7-th place in terms of score...

gd_barnes 2008-08-20 11:06

[quote=Cruelty;139473]According to PrimeGrid news they have found a new "321" prime. This will most likely put RPS on the 7-th place in terms of score...[/quote]


At this point, I thought that Primegrid would get full credit for the prime. I think the 321search project stopped at n=5M. (Anyone know for sure?)

You are correct, RPS lead over 321search is 4993-2608 or a 2385 difference. Assuming half-credit, it would take a prime with a score of 4770 for 321search to overtake RPS, which an exponent of n=~5.4M should be.

But I'm sure it wouldn't take long for RPS to hop back into 6th again. :smile:

mdettweiler 2008-08-20 14:50

[quote=gd_barnes;139542]At this point, I thought that Primegrid would get full credit for the prime. I think the 321search project stopped at n=5M. (Anyone know for sure?)

You are correct, RPS lead over 321search is 4993-2608 or a 2385 difference. Assuming half-credit, it would take a prime with a score of 4770 for 321search to overtake RPS, which an exponent of n=~5.4M should be.

But I'm sure it wouldn't take long for RPS to hop back into 6th again. :smile:[/quote]
I hear PrimeGrid has now held off on 3*2^n-1 for the time being--now they're doing 3*2^n+1 until it's caught up with the former. So, that's probably what they found, in which case they would get full credit, because 3*2^n+1 is a project they're doing all on their own.

axn 2008-08-20 21:16

[QUOTE=Anonymous;139551]I hear PrimeGrid has now held off on 3*2^n-1 for the time being--now they're doing 3*2^n+1 until it's caught up with the former. So, that's probably what they found, in which case they would get full credit, because 3*2^n+1 is a project they're doing all on their own.[/QUOTE]

[url]http://primes.utm.edu/primes/page.php?id=85438[/url]

kar_bon 2008-08-28 10:35

another one from Benson: 9*2^2060941-1 [url]http://primes.utm.edu/primes/page.php?id=85462[/url]

Kosmaj 2008-09-16 21:19

First primes with more than 10M digits
 
Two new, huge Mersenne primes!

2^43112609-1, 12978189 digits, found on August 23
2^37156667-1, 11185272 digits, found on September 6

Kosmaj 2008-11-07 03:22

New Gen Woodall Record
 
Congrats to Hugo (p237) on the new GW record!

[URL="http://primes.utm.edu/primes/page.php?id=85721"]189620*19^189620-1[/URL] (242483 digits).

Cruelty 2008-11-16 08:32

[URL="http://primes.utm.edu/primes/page.php?id=85758"]The first non-Mersenne megaprime from Curtis Cooper[/URL] :tu:

Kosmaj 2008-11-16 08:56

Yes, the 21st prime with more than 1 million digits, and potentially the new largest Fermat (or Gen. Fermat) divisor because of a smal K:

7*2^3511774+1 (1057151 digits)

I wonder why did he use an "x" prover's code, meaning a new search algorithm?

amphoria 2008-11-16 14:50

I sse its now been corrected and changed to OpenPFGW.

em99010pepe 2008-11-19 13:25

[url=http://primes.utm.edu/primes/page.php?id=85789]5*2^2460482-1[/url]

em99010pepe 2008-11-24 11:39

My friend Benson strikes again.

5*2^3059698-1
[URL]http://primes.utm.edu/primes/page.php?id=85814[/URL]

Cruelty 2008-12-14 15:57

Another k=4, b=3 prime
 
4*3^416337-1 (198644 digits) :smile:

Cruelty 2008-12-15 10:57

Another big [URL="http://primes.utm.edu/primes/page.php?id=85944"]prime[/URL] :tu:

kar_bon 2008-12-15 12:26

[QUOTE=Cruelty;153404]Another big [URL="http://primes.utm.edu/primes/page.php?id=85944"]prime[/URL] :tu:[/QUOTE]

see the Constant-n Search page here [url]http://www.rieselprime.de/Data/Constant_n.htm[/url]

Thomas11 2008-12-18 17:51

[URL="http://primes.utm.edu/primes/page.php?id=85969"]1003*2^2076535-1[/URL]

em99010pepe 2009-01-05 10:04

My friend Benson strikes again.

5*2^3569154-1
[U][url]http://primes.utm.edu/primes/page.php?id=86152[/url][/U]

henryzz 2009-01-05 13:16

he has had a lot of luck lately

Cruelty 2009-01-09 01:28

4*3^423253-1 (201944 digits) :smile:

Beyond 2009-02-10 01:28

Looks like the 12121 search may have found a 1 million digit prime [url]http://primes.utm.edu/primes/page.php?id=86608[/url]

Kosmaj 2009-02-10 08:35

The verification failed :sad:

The question now is whether it was a typo, or a software or hardware error.

Anyway, I wish them to find their first mega-digit prime soon!

Kosmaj 2009-04-21 06:13

Cullen record
 
Congrats to PrimeGrid on the new record Cullen prime:

[URL="http://primes.utm.edu/primes/page.php?id=87775"]6328548*2^6328548+1 [/URL]

kar_bon 2009-06-14 13:18

a new Mersenne prime was verified : [url=http://primes.utm.edu/primes/page.php?id=88847]2^42643801-1[/url]!

Uncwilly 2009-06-14 13:33

[QUOTE=kar_bon;177533]a new Mersenne prime was verified : [url=http://primes.utm.edu/primes/page.php?id=88847]2^42643801-1[/url]![/QUOTE]However, we are finding them fast enough, that Caldwell is having trouble keeping up his pages. There are places where he refers to 43 known MP's.

Harvey563 2009-06-24 22:41

Near Generalized Woodall
 
45444*512^45443-1

kar_bon 2009-06-24 23:49

[QUOTE=Harvey563;178753]45444*512^45443-1[/QUOTE]

so this is a new entry for [url]http://www.geocities.com/harvey563/NearCullen_WoodallPrimes.txt[/url]

as 11361*2^408989-1 with 123123 digits!

why this prime wasn't found before although the high limit on the above link is given as n=543000!?

so this range only counts for base=2, but not others.
and the special base 512 -> 2^9 makes this prime more harder to find.

so the 'normal' sieve is for (n+1)*2^n-1,
but for a base with power x of 2 someone has to sieve: (n+1)*2^(n*x)-1!?

for example x=10 the sieve/test for n+1 Near Woodall is like:

1001*2^10000-1
1002*2^10010-1
1003*2^10020-1
and so on.

correct? or i'm totally wrong here?

Kosmaj 2009-06-25 00:45

[QUOTE]so this is a new entry for [url]http://www.geocities.com/harvey563/N...dallPrimes.txt[/url][/QUOTE]

No it's not. The link lists "Near-Cullen & Near-Woodall primes" (see the title) considering only base 2, while the reported prime is [U]Generalized[/U] near Woodal, to base 512.

Harvey563 2009-07-07 20:04

New Near Generalized Woodall
 
80472*256^80473-1 Near Generalized Woodall


Sieved with Rodenkirch's Multisieve.


:hello:


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