A382997 a(n) = -Sum_{d|n} phi(n/d) * (-n)^d.

1, -2, 33, -264, 3145, -46500, 823585, -16781408, 387422001, -9999900360, 285311670721, -8916103472496, 302875106592409, -11112006720145604, 437893890382391745, -18446744078004650880, 827240261886336764449, -39346408075098246299676, 1978419655660313589124321

Offset: 1

Author

Seiichi Manyama, Apr 12 2025

Keywords

• sign

Crossrefs

Main diagonal of A382994.

Cf. A000010, A383010.

Programs

PARI

a(n) = -sumdiv(n, d, eulerphi(n/d)*(-n)^d);

Formula

a(n) = -Sum_{k=1..n} (-n)^gcd(n,k).