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A292302 Expansion of (1 - x)*Sum_{k>=1} k*phi(k)*x^k/(1 - x^k), where phi() is the Euler totient function (A000010). 0
1, 2, 4, 4, 10, 0, 22, 0, 18, 2, 48, -34, 80, -28, 18, 24, 102, -90, 160, -112, 70, 32, 174, -206, 220, -50, 76, -74, 340, -372, 490, -248, 94, 42, 84, -232, 662, -304, 70, -196, 738, -738, 904, -586, 60, 240, 642, -966, 904, -538, 348, -184, 1030, -1116, 690, -482, 552, 38, 984, -1806 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

First differences of A057660.

LINKS

Table of n, a(n) for n=1..60.

FORMULA

G.f.: (1 - x)*Sum_{k>=1} k*phi(k)*x^k/(1 - x^k).

MATHEMATICA

nmax = 60; Rest[CoefficientList[Series[(1 - x) Sum[EulerPhi[k] k x^k /(1 - x^k), {k, 1, nmax}], {x, 0, nmax}], x]]

CROSSREFS

Cf. A057660, A174405.

Sequence in context: A039887 A216162 A114215 * A151712 A253827 A186987

Adjacent sequences:  A292299 A292300 A292301 * A292303 A292304 A292305

KEYWORD

sign

AUTHOR

Ilya Gutkovskiy, Sep 14 2017

STATUS

approved

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Last modified June 3 07:14 EDT 2020. Contains 334799 sequences. (Running on oeis4.)