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A152057 Sum of the distinct prime factors of 2^n-1. 1
0, 0, 3, 7, 8, 31, 10, 127, 25, 80, 45, 112, 28, 8191, 173, 189, 282, 131071, 102, 524287, 91, 471, 798, 178528, 286, 2433, 10925, 262737, 320, 3425, 534, 2147483647, 65819, 599598, 174765, 123150, 266, 616318400, 699053, 129646, 61789, 164524720, 5936 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..42.

MATHEMATICA

Table[Sum[FactorInteger[2^n - 1][[m]][[1]], {m, 1, Length[FactorInteger[2^n - 1]]}], {n, 0, 50}]

CROSSREFS

Cf. A046800, A075708, A000079.

Sequence in context: A152486 A301523 A105756 * A177689 A191611 A281678

Adjacent sequences:  A152054 A152055 A152056 * A152058 A152059 A152060

KEYWORD

nonn

AUTHOR

Roger L. Bagula, Nov 22 2008

EXTENSIONS

Edited by N. J. A. Sloane, Nov 26 2008

STATUS

approved

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Last modified December 10 04:15 EST 2019. Contains 329885 sequences. (Running on oeis4.)