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
Keywords
Links
- Seiichi Manyama, Table of n, a(n) for n = 1..351
Programs
-
PARI
a(n) = sumdiv(n, d, (2*d+1)^n);
Formula
a(n) = Sum_{k=0..n} 2^k * binomial(n,k) * sigma_k(n).