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Beyond 2009-02-10 01:28

Looks like the 12121 search may have found a 1 million digit prime [url][/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=""]6328548*2^6328548+1 [/URL]

kar_bon 2009-06-14 13:18

a new Mersenne prime was verified : [url=]2^42643801-1[/url]!

Uncwilly 2009-06-14 13:33

[QUOTE=kar_bon;177533]a new Mersenne prime was verified : [url=]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

kar_bon 2009-06-24 23:49


so this is a new entry for [url][/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:

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][/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.


em99010pepe 2009-08-02 19:56

From PrimeGrid....

[quote]World Record Cullen Mega Prime returned
2009-08-01 15:40 UTC
As unbelievable as it may sound, another Cullen Mega Prime has been discovered!!! It is only the 16th known Cullen prime. It is also a top 15 prime at over 2M digits and the largest found by LLR. Additionally, it is PrimeGrid's largest prime to date. The discoverer is from Japan and a member of [URL=""]Team 2ch[/URL]. Verification is in progress. Stay tuned for more details.

Kosmaj 2009-09-19 01:02

Congrats to Tom [L983] on the new Sophie Germain record!


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