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A023595 a(n) = sum of exponents in prime-power factorization of 2*prime(n)+1. 2
1, 1, 1, 2, 1, 3, 2, 2, 1, 1, 3, 3, 1, 2, 2, 1, 2, 2, 4, 2, 3, 2, 1, 1, 3, 2, 3, 2, 2, 1, 3, 1, 3, 3, 2, 2, 4, 2, 2, 1, 1, 3, 1, 3, 2, 3, 3, 2, 3, 4, 1, 1, 3, 1, 2, 2, 3, 2, 3, 1, 5, 1, 3, 2, 3, 2, 3, 5, 2, 2, 2, 1, 4, 3, 3, 2, 2, 3, 2, 4, 1, 2, 1, 3, 2, 1, 2, 3, 2, 3, 3, 2, 4, 1, 4, 2, 1, 2, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..99.

MATHEMATICA

Array[Plus@@Last/@FactorInteger[2*Prime[ # ]+1]&, 6! ] (* Vladimir Joseph Stephan Orlovsky, Feb 28 2010 *)

Total[FactorInteger[#][[All, 2]]]&/@(2*Prime[Range[100]]+1) (* Harvey P. Dale, Oct 02 2017 *)

CROSSREFS

Sequence in context: A290536 A277855 A136662 * A177718 A057515 A300712

Adjacent sequences:  A023592 A023593 A023594 * A023596 A023597 A023598

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified January 25 01:49 EST 2020. Contains 331229 sequences. (Running on oeis4.)