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A327274 Dirichlet g.f.: 1 / (zeta(s)^2 * (1 - 2^(1 - s))). 1
1, 0, -2, 1, -2, 0, -2, 2, 1, 0, -2, -2, -2, 0, 4, 4, -2, 0, -2, -2, 4, 0, -2, -4, 1, 0, 0, -2, -2, 0, -2, 8, 4, 0, 4, 1, -2, 0, 4, -4, -2, 0, -2, -2, -2, 0, -2, -8, 1, 0, 4, -2, -2, 0, 4, -4, 4, 0, -2, 4, -2, 0, -2, 16, 4, 0, -2, -2, 4, 0, -2, 2, -2, 0, -2, -2, 4, 0, -2, -8 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Dirichlet inverse of A048272.

Moebius transform of A067856.

LINKS

Table of n, a(n) for n=1..80.

FORMULA

a(1) = 1; a(n) = -Sum_{d|n, d<n} A048272(n/d) * a(d).

a(n) = Sum_{d|n} mu(n/d) * A067856(d).

MATHEMATICA

a[1] = 1; a[n_] := Sum[Sum[(-1)^j, {j, Divisors[n/d]}] a[d], {d, Most @ Divisors[n]}]; Table[a[n], {n, 1, 80}]

CROSSREFS

Cf. A007427, A008683, A048272, A062503 (positions of 1's), A067856, A327268.

Sequence in context: A151676 A151684 A118207 * A055378 A217921 A272328

Adjacent sequences:  A327271 A327272 A327273 * A327275 A327276 A327277

KEYWORD

sign,mult

AUTHOR

Ilya Gutkovskiy, Oct 22 2019

STATUS

approved

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Last modified January 23 01:15 EST 2020. Contains 331166 sequences. (Running on oeis4.)