A347399 a(n) = A347398(n^n).

1, 5, 28, 261, 3126, 46688, 823544, 16777477, 387420517, 10000003386, 285311670612, 8916117272416, 302875106592254, 11112006826381820, 437893890380862528, 18446744073726329093, 827240261886336764178, 39346408075296925042857

Offset: 1

Author

Seiichi Manyama, Aug 30 2021

Keywords

• nonn

Comments

This sequence is different from A062796.

Crossrefs

Cf. A000312, A062796, A347397, A347398.

Programs

PARI

a(n) = sum(k=1, n, (n^n%k^k==0)*k^k);

Formula

a(n) = A347397(n^n) - A347397(n^n-1) for n > 1.

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

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