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-   -   History (https://www.mersenneforum.org/showthread.php?t=17188)

ET_ 2012-09-13 18:32

History
 
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

LaurV 2012-09-14 04:46

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? :razz:

LaurV 2012-09-14 06:48

Went to the page:

[QUOTE]In mathematics, a [B]double Mersenne number[/B] is a Mersenne number of the form:
MMp = 22p-1 - 1
where [COLOR=Red][B]p[/B][/COLOR] is a Mersenne number.[/QUOTE]

Shouldn't say Mp? Or more generally, Mn?

ET_ 2012-09-14 08:37

[QUOTE=LaurV;311556]Went to the page:



Shouldn't say Mp? Or more generally, Mn?[/QUOTE]

Correct. Thank you.

Luigi

ET_ 2012-09-14 23:33

Private communication from Landon Curt Noll
 
I just read this sentence: "In private correspondence with Chris K. Caldwell, I announced that [COLOR="Red"]C[sub]5[/sub] = 2[sup](2[sup]127[/sup]-1)[/sup]-1 has no prime factor < 5 * 10[sup]51[/sup].[/COLOR]"

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

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

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

Luigi

Prime95 2012-09-15 03:31

[QUOTE=ET_;311666]I just read this sentence: "In private correspondence with Chris K. Caldwell, I announced that [COLOR="Red"]C[sub]5[/sub] = 2[sup](2[sup]127[/sup]-1)[/sup]-1 has no prime factor < 5 * 10[sup]51[/sup].[/COLOR]"[/QUOTE]

Thats only 2^171.7. Ernst later went to about 2^175.5

aketilander 2012-09-15 06:17

[QUOTE=ET_;311465]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[/QUOTE]

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:

[URL]http://www.garlic.com/~wedgingt/MMPstats.txt[/URL]

Ralf Recker 2012-09-15 06:48

[QUOTE=aketilander;311693]Is there / will there be a special website for "the search of Double Mersennes" like for "Operation Billion Digits"?[/QUOTE]

[URL]http://www.moregimps.it/doublemersennes/index.php[/URL] <--- obsolete!
[URL]http://www.doublemersennes.org[/URL]

axn 2012-09-15 07:05

[QUOTE=LaurV;311556]Went to the page:



Shouldn't say Mp? Or more generally, Mn?[/QUOTE]

[QUOTE=ET_;311565]Correct. Thank you.

Luigi[/QUOTE]

"... where Mp is a Mersenne [B]prime[/B]" would be more accurate.

LaurV 2012-09-15 07:13

[QUOTE=axn;311701]"... where Mp is a Mersenne [B]prime[/B]" would be more accurate.[/QUOTE]
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.

ET_ 2012-09-15 11:09

[QUOTE=Prime95;311685]Thats only 2^171.7. Ernst later went to about 2^175.5[/QUOTE]

You (and science_man_88 who PMed me) are right.

But a factor f=5*10[sup]51[/sup] should have k equal to 1500000000000, not 3000000000000...

Am I missing the point?

Luigi


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