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Old 2017-01-12, 08:38   #1
Kalli Hofmann
 
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"Karl-Heinz Hofmann"
Jan 2017
Gr.-Rohrheim Germany

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Default Why is that Factor not listed ?

On the page :
http://www.mersenne.ca/exponent.php?exponentdetails=47
only two factors are listed. But M47 is fully factored.
The factor 13264529 is missing for completness.
Why is it not listed ?
Greetings from Germany ..... Kalli
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Old 2017-01-12, 15:55   #2
Batalov
 
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"Serge"
Mar 2008
Phi(4,2^7658614+1)/2

100011101001012 Posts
Default

For most "completely factored" * numbers listed on that page, last factor (a.k.a. "cofactor") is by convention not shown (because it would take pages to show, except for very small entries):
E.g. if
M... = a * b * c * cofactor
then
a, b and c prime factors are listed, and for cofactor search for the line
Remaining cofactor is a probable-prime

Furthermore, in the "Composite Factors" section, only combinations a*b, a*c, b*c will be shown but not "a*cofactor". "It is a feature, not a bug", as they say.
_______________
* there is controversy about the use of this term :-) hence it is in quotes.
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Old 2017-01-13, 08:18   #3
Kalli Hofmann
 
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"Karl-Heinz Hofmann"
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Thank you BATALOV Indeed, those Factors can be very big ...... But M47 has only three factors, and the last Factor seems not too big for me. (13264529). What a pity
In Germany we say: "es es, wie es es" ... in english : "it is, how it is"
Thank you ........................ Kalli
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Old 2017-01-13, 08:37   #4
Kalli Hofmann
 
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"Karl-Heinz Hofmann"
Jan 2017
Gr.-Rohrheim Germany

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Default

On this page:
http://www.mersenne.ca/prp.php?show=...onent=1000#M47
The last Faktor is listed.
Another Question: when look at the M59, you see PRP-13, as remaining cofactor. Is there a list, where you can see, how those PRPĀ“s look like ?
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Old 2017-01-13, 08:59   #5
axn
 
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Jun 2003

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http://www.factordb.com/index.php?query=M59
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