A347251 a(n) = Sum_{d|n} mu(d)*mu(n/d)*d^n.

1, -5, -28, 16, -3126, 47450, -823544, 0, 19683, 10009766650, -285311670612, -2176786432, -302875106592254, 11112685048647250, 437893920912786408, 0, -827240261886336764178, -101560344088905, -1978419655660313589123980, -100000000000001048576

Offset

1,2

Links

Seiichi Manyama, Table of n, a(n) for n = 1..388

Formula

If p is prime, a(p) = -1 - p^p.

Mathematica

a[n_] := DivisorSum[n, MoebiusMu[#] * MoebiusMu[n/#] * #^n &]; Array[a, 20] (* Amiram Eldar, Aug 24 2021 *)

Prog

(PARI) a(n) = sumdiv(n, d, moebius(d)*moebius(n/d)*d^n);

Crossrefs

Diagonal of A347227.

Cf. A007427, A008683, A046099, A067858, A321222.

Sequence in context: A052470 A351749 A016087 * A321236 A351774 A344579

Adjacent sequences: A347248 A347249 A347250 * A347252 A347253 A347254

Keyword

sign

Author

Seiichi Manyama, Aug 24 2021

Status

approved