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A192895 A000120-deficiency of n. 6
-1, 0, -1, 1, -1, 2, -2, 2, 1, 2, -2, 5, -2, 2, 1, 3, -1, 6, -2, 5, 3, 2, -3, 8, 0, 2, 1, 6, -3, 10, -4, 4, 4, 2, 3, 11, -2, 2, 2, 8, -2, 12, -3, 6, 7, 2, -4, 11, 1, 6, 1, 6, -3, 10, 1, 10, 2, 2, -4, 19, -4, 2, 5, 5, 4, 12, -2, 5, 4, 12, -3, 16, -2, 2, 8, 6 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

COMMENTS

a(n) = Sum(A000120(d): 1 <= d < n and n mod d = 0) - A000120(n); see A175522 for motivation and more information;

a(A175524(n)) < 0; a(A175522(n)) = 0; a(A175526(n)) > 0.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

MATHEMATICA

a[n_] := DivisorSum[n, Total[IntegerDigits[#, 2]]*(-1)^Boole[# == n]&]; Array[a, 80] (* Jean-Fran├žois Alcover, Dec 05 2015, adapted from PARI *)

PROG

(Haskell)

a192895 n =

   sum (map a000120 $ filter ((== 0) . (mod n)) [1..n-1]) - a000120 n

a192895_list = map a192895 [1..]

(PARI) a(n)=sumdiv(n, d, hammingweight(d)*(-1)^(d==n)) \\ Charles R Greathouse IV, Feb 07 2013

CROSSREFS

Cf. A033879.

Sequence in context: A261915 A109037 A147680 * A210685 A264051 A120965

Adjacent sequences:  A192892 A192893 A192894 * A192896 A192897 A192898

KEYWORD

sign

AUTHOR

Reinhard Zumkeller, Jul 12 2011

STATUS

approved

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Last modified August 19 13:00 EDT 2017. Contains 290807 sequences.