A076723 Sum_{d divides n} (-d)^d.

-1, 3, -28, 259, -3126, 46632, -823544, 16777475, -387420517, 9999996878, -285311670612, 8916100495144, -302875106592254, 11112006824734476, -437893890380862528, 18446744073726329091, -827240261886336764178, 39346408075296150201567

Offset: 1

Author

Vladeta Jovovic, Oct 27 2002

Keywords

• sign

Links

• Seiichi Manyama, Table of n, a(n) for n = 1..386

Crossrefs

Cf. A062796, A321385.

Programs

PARI

a(n) = sumdiv(n, d, (-d)^d); \\ Michel Marcus, Dec 22 2018

Formula

G.f.: Sum_{n>0} (-n*x)^n/(1-x^n).