A350008 a(n) = Sum_{k=0..n} k^(2*k).

1, 2, 18, 747, 66283, 9831908, 2186614244, 680409687093, 282155386397749, 150376790683396870, 100150376790683396870, 81502899763630444510191, 79578350103154474577951727, 91812908543371771132977567736

Offset: 0

Author

Seiichi Manyama, Dec 08 2021

Keywords

• nonn

Comments

Partial sums of A062206.

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..214

Crossrefs

Cf. A000330, A062206, A062970, A100262, A249459, A349962.

Programs

Mathematica

a[n_] := Sum[If[k == 0, 1, k^(2*k)], {k, 0, n}]; Array[a, 14, 0] (* Amiram Eldar, Dec 08 2021 *)

PARI

a(n) = sum(k=0, n, k^(2*k));

Formula

a(n) ~ n^(2*n). - Vaclav Kotesovec, Dec 08 2021