A342423 a(n) = Sum_{k=1..n} gcd(k,n)^gcd(k,n).

1, 5, 29, 262, 3129, 46693, 823549, 16777484, 387420549, 10000003145, 285311670621, 8916100495490, 302875106592265, 11112006826381589, 437893890380865741, 18446744073726329368, 827240261886336764193, 39346408075296925089309

Offset

1,2

Links

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

Formula

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

Mathematica

a[n_] := Sum[GCD[k, n]^GCD[k, n], {k, 1, n}]; Array[a, 18] (* Amiram Eldar, Mar 11 2021 *)

Prog

(PARI) a(n) = sum(k=1, n, gcd(k, n)^gcd(k, n));
(PARI) a(n) = sumdiv(n, d, eulerphi(n/d)*d^d);

Crossrefs

Cf. A000010, A332517, A342420, A342424.

Sequence in context: A370768 A231712 A215867 * A342449 A345098 A144015

Adjacent sequences: A342420 A342421 A342422 * A342424 A342425 A342426

Keyword

nonn

Author

Seiichi Manyama, Mar 11 2021

Status

approved