A292302 Expansion of (1 - x)*Sum_{k>=1} k*phi(k)*x^k/(1 - x^k), where phi() is the Euler totient function (A000010).

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

Offset: 1

Author

Ilya Gutkovskiy, Sep 14 2017

Keywords

• sign

Comments

First differences of A057660.

Crossrefs

Cf. A057660, A174405.

Programs

Mathematica

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

Formula

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