OFFSET
0,3
FORMULA
a(n) ~ A309419 * n^n. - Vaclav Kotesovec, Dec 26 2023
PROG
(PARI) a(n) = sum(k=0, n, 2^(n-k)*k^n);
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Seiichi Manyama, Dec 25 2023
STATUS
approved