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Old 2012-09-13, 18:32   #1
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Put on this thread whatever you know about the history of the search of Double Mersennes.

I will check from time to time, and insert the most interesting items on the website.

Lugi
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Old 2012-09-14, 04:46   #2
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well, for me it happen more often, when I have to sign official papers with full name... I have a very long name (my parent's fantasies)

but... Lugi?
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Old 2012-09-14, 06:48   #3
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Went to the page:

Quote:
In mathematics, a double Mersenne number is a Mersenne number of the form:
MMp = 22p-1 - 1
where p is a Mersenne number.
Shouldn't say Mp? Or more generally, Mn?
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Old 2012-09-14, 08:37   #4
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Quote:
Originally Posted by LaurV View Post
Went to the page:



Shouldn't say Mp? Or more generally, Mn?
Correct. Thank you.

Luigi
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Old 2012-09-14, 23:33   #5
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Default Private communication from Landon Curt Noll

I just read this sentence: "In private correspondence with Chris K. Caldwell, I announced that C5 = 2(2[sup]127-1)[/sup]-1 has no prime factor < 5 * 1051."

The links are:
http://www.isthe.com/chongo/bio.html#publications
http://www.isthe.com/chongo/tech/math/prime/index.html

Here is Chris Caldwell publication about his claim:
http://primes.utm.edu/mersenne/index.html#c

Is there any official paper about it?
I tried to email Mr. Noll asking for some more infos...

Luigi

Last fiddled with by ET_ on 2012-09-14 at 23:50
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Old 2012-09-15, 03:31   #6
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Quote:
Originally Posted by ET_ View Post
I just read this sentence: "In private correspondence with Chris K. Caldwell, I announced that C5 = 2(2[sup]127-1)[/sup]-1 has no prime factor < 5 * 1051."
Thats only 2^171.7. Ernst later went to about 2^175.5
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Old 2012-09-15, 06:17   #7
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Quote:
Originally Posted by ET_ View Post
Put on this thread whatever you know about the history of the search of Double Mersennes.

I will check from time to time, and insert the most interesting items on the website.

Lugi
Is there / will there be a special website for "the search of Double Mersennes" like for "Operation Billion Digits"?

If there is already please post a link.

The only such site I know about is Will Edgingtons:

http://www.garlic.com/~wedgingt/MMPstats.txt

Last fiddled with by aketilander on 2012-09-15 at 06:19
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Old 2012-09-15, 06:48   #8
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Quote:
Originally Posted by aketilander View Post
Is there / will there be a special website for "the search of Double Mersennes" like for "Operation Billion Digits"?
http://www.moregimps.it/doublemersennes/index.php <--- obsolete!
http://www.doublemersennes.org

Last fiddled with by ET_ on 2012-09-24 at 11:44 Reason: Updated link
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Old 2012-09-15, 07:05   #9
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Quote:
Originally Posted by LaurV View Post
Went to the page:



Shouldn't say Mp? Or more generally, Mn?
Quote:
Originally Posted by ET_ View Post
Correct. Thank you.

Luigi
"... where Mp is a Mersenne prime" would be more accurate.
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Old 2012-09-15, 07:13   #10
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Quote:
Originally Posted by axn View Post
"... where Mp is a Mersenne prime" would be more accurate.
No. The definition should say nothing about primality. Mersenne numbers Mp are defined for all p, not only for primes. Later on, there is usually a discussion about when a mersenne number can be prime and when it can not, but primality of p should not be required in the definition. A double mersenne number is just a mersenne number whose exponent is also a mersenne number.

Last fiddled with by LaurV on 2012-09-15 at 07:13
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Old 2012-09-15, 11:09   #11
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Quote:
Originally Posted by Prime95 View Post
Thats only 2^171.7. Ernst later went to about 2^175.5
You (and science_man_88 who PMed me) are right.

But a factor f=5*1051 should have k equal to 1500000000000, not 3000000000000...

Am I missing the point?

Luigi
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