The nature of the "double check" - Page 2

science_man_88 · 2016-03-11, 14:33

Quote:

Originally Posted by ATH

Actually a "Mersenne Number" is 2ⁿ-1 not 2^p - 1:

http://mathworld.wolfram.com/MersenneNumber.html

Quote:

Since the most interest in Mersenne numbers arises from attempts to factor them, many authors prefer to define a Mersenne number as a number of the above form

$M_p=2^p-1$ ,
(14)
but with p restricted to prime values.

from your link. though maybe it's an incorrect source as

Quote:

where n is an integer.

should mean $2^{-1}-1 = 1/2 -1 = -1/2$ is also a mersenne as well as any fraction of form -(2^n-1)/(2^n)

LaurV · 2016-03-11, 15:01

Quote:

Originally Posted by ATH

Actually a "Mersenne Number" is 2ⁿ-1 not 2^p - 1:

http://mathworld.wolfram.com/MersenneNumber.html

I subscribe to the first definition too (n positive integer, not necessarily prime), however we (and wolfram too) are in minority. Most of the authors require the exponent to be prime. This was discussed on forum in the past, and I already expressed my preference.

PawnProver44 · 2016-03-11, 16:52

The "p" refers to the exponent being prime. "n" is the general definition of Mersenne Numbers.

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2016-03-11, 16:52	#14
PawnProver44 "NOT A TROLL" Mar 2016 California 305₈ Posts	The "p" refers to the exponent being prime. "n" is the general definition of Mersenne Numbers.