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
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Nov 21 2023
STATUS
approved