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Old 2009-02-10, 01:28   #89
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Looks like the 12121 search may have found a 1 million digit prime http://primes.utm.edu/primes/page.php?id=86608
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Old 2009-02-10, 08:35   #90
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The verification failed

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!
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Old 2009-04-21, 06:13   #91
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Default Cullen record

Congrats to PrimeGrid on the new record Cullen prime:

6328548*2^6328548+1

Last fiddled with by Kosmaj on 2009-05-18 at 10:07
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Old 2009-06-14, 13:18   #92
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a new Mersenne prime was verified : 2^42643801-1!
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Old 2009-06-14, 13:33   #93
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Quote:
Originally Posted by kar_bon View Post
a new Mersenne prime was verified : 2^42643801-1!
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.

Last fiddled with by Uncwilly on 2009-06-14 at 13:34
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Old 2009-06-24, 22:41   #94
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Red face Near Generalized Woodall

45444*512^45443-1
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Old 2009-06-24, 23:49   #95
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Quote:
Originally Posted by Harvey563 View Post
45444*512^45443-1
so this is a new entry for http://www.geocities.com/harvey563/N...dallPrimes.txt

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?
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Old 2009-06-25, 00:45   #96
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Quote:
so this is a new entry for http://www.geocities.com/harvey563/N...dallPrimes.txt
No it's not. The link lists "Near-Cullen & Near-Woodall primes" (see the title) considering only base 2, while the reported prime is Generalized near Woodal, to base 512.

Last fiddled with by Kosmaj on 2009-06-25 at 00:46
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Old 2009-07-07, 20:04   #97
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Default New Near Generalized Woodall

80472*256^80473-1 Near Generalized Woodall


Sieved with Rodenkirch's Multisieve.


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Old 2009-08-02, 19:56   #98
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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 Team 2ch. Verification is in progress. Stay tuned for more details.
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Old 2009-09-19, 01:02   #99
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Congrats to Tom [L983] on the new Sophie Germain record!

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