A339702 Dirichlet g.f.: Product_{k>=2} (1 - k^(-s))^3.

1, -3, -3, 0, -3, 6, -3, 5, 0, 6, -3, 6, -3, 6, 6, 0, -3, 6, -3, 6, 6, 6, -3, -9, 0, 6, 5, 6, -3, -3, -3, 0, 6, 6, 6, -9, -3, 6, 6, -9, -3, -3, -3, 6, 6, 6, -3, -9, 0, 6, 6, 6, -3, -9, 6, -9, 6, 6, -3, -21, -3, 6, 6, -7, 6, -3, -3, 6, 6, -3, -3, -12, -3, 6, 6, 6, 6, -3, -3, -9

Offset: 1

Author

Ilya Gutkovskiy, Dec 13 2020

Keywords

• sign

Crossrefs

Cf. A010816, A114592, A339318, A339701, A339703, A339704, A339705, A339706, A339707.

Formula

a(1) = 1; a(n) = -Sum_{d|n, d < n} A339318(n/d) * a(d).

a(p^k) = A010816(k) for prime p.