A367509 a(n) = Sum_{d|n} (2*d+1)^n.

3, 34, 370, 7267, 161294, 4960812, 170861562, 7019201348, 322728071069, 16705828227476, 952809758091074, 59628239376008854, 4052555153020570590, 297587425607933152700, 23465266173840431204452, 1978033864507607364591749, 177482997121587371955312038

Offset

1,1

Links

Seiichi Manyama, Table of n, a(n) for n = 1..351

Formula

a(n) = Sum_{k=0..n} 2^k * binomial(n,k) * sigma_k(n).

Prog

(PARI) a(n) = sumdiv(n, d, (2*d+1)^n);

Crossrefs

Cf. A163190, A367510.

Sequence in context: A268802 A284891 A231593 * A134491 A045727 A105713

Adjacent sequences: A367506 A367507 A367508 * A367510 A367511 A367512

Keyword

nonn

Author

Seiichi Manyama, Nov 21 2023

Status

approved