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A327268 Dirichlet g.f.: 1 / (zeta(s) * zeta(s-1) * (1 - 2^(2 - s))). 2
1, 1, -4, 6, -6, -4, -8, 24, 3, -6, -12, -24, -14, -8, 24, 96, -18, 3, -20, -36, 32, -12, -24, -96, 5, -14, 0, -48, -30, 24, -32, 384, 48, -18, 48, 18, -38, -20, 56, -144, -42, 32, -44, -72, -18, -24, -48, -384, 7, 5, 72, -84, -54, 0, 72, -192, 80, -30, -60, 144, -62, -32, -24, 1536, 84 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Dirichlet inverse of A002129.

LINKS

Georg Fischer, Table of n, a(n) for n = 1..1000

FORMULA

a(1) = 1; a(n) = -Sum_{d|n, d<n} A002129(n/d) * a(d).

MATHEMATICA

a[1] = 1; a[n_] := Sum[Sum[(-1)^j j, {j, Divisors[n/d]}] a[d], {d, Most @ Divisors[n]}]; Table[a[n], {n, 1, 65}]

CROSSREFS

Cf. A002129, A046692, A327274, A327278.

Sequence in context: A286720 A201393 A327721 * A146208 A011227 A155907

Adjacent sequences:  A327265 A327266 A327267 * A327269 A327270 A327271

KEYWORD

sign,mult

AUTHOR

Ilya Gutkovskiy, Oct 22 2019

STATUS

approved

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Last modified December 16 06:18 EST 2019. Contains 330016 sequences. (Running on oeis4.)