A357922 a(n) = Sum_{k=0..floor(n/5)} |Stirling1(n - 4*k,k)|.

1, 0, 0, 0, 0, 1, 1, 2, 6, 24, 121, 723, 5051, 40370, 363154, 3630565, 39929874, 479111219, 6228047601, 87188921464, 1307794924973, 20924276449014, 355707232027825, 6402657184129671, 121649439722758345, 2432972744390660437, 51092165603897459951

Offset

0,8

Links

Table of n, a(n) for n=0..26.

Formula

G.f.: Sum_{k>=0} x^k * Product_{j=0..k-1} (j + x^4).

Prog

(PARI) a(n) = sum(k=0, n\5, abs(stirling(n-4*k, k, 1)));
(PARI) my(N=30, x='x+O('x^N)); Vec(sum(k=0, N, x^k*prod(j=0, k-1, j+x^4)))

Crossrefs

Cf. A000142, A343579, A357901, A357902.

Cf. A357920.

Sequence in context: A230363 A358500 A358494 * A275753 A349089 A352429

Adjacent sequences: A357919 A357920 A357921 * A357923 A357924 A357925

Keyword

nonn

Author

Seiichi Manyama, Oct 20 2022

Status

approved