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

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!

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]

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

[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.

Near Generalized Woodall
 

45444*512^45443-1

[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?

[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.

New Near Generalized Woodall
 

80472*256^80473-1 Near Generalized Woodall


Sieved with Rodenkirch's Multisieve.


:hello:

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="http://www.primegrid.com/team_display.php?teamid=194"]Team 2ch[/URL]. Verification is in progress. Stay tuned for more details.
[/quote]

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

607095*2^176311-1
607095*2^176312-1