A086555 E.g.f. satisfies F(x) = 1/2 * (F(-log(1-x)) + x).

1, 1, 5, 47, 719, 16299, 513253, 21430513, 1145710573, 76317960163, 6197399680779, 602640663660199, 69134669061681469, 9239224408001877873, 1422887941494773642817, 250160794466824215921275

Offset

1,3

Links

Vaclav Kotesovec, Table of n, a(n) for n = 1..250

Formula

a(n) = Sum_{k=1..n-1} |Stirling1(n, k)|*a(k).

a(n) ~ A260932 * n!^2 / (2^n * log(2)^n * n^(1 - log(2)/3)). - Vaclav Kotesovec, Jul 01 2025

Mathematica

Clear[a]; a[1] = 1; a[n_] := a[n] = Sum[Abs[StirlingS1[n, k]]*a[k], {k, 1, n-1}]; Table[a[n], {n, 1, 20}] (* Vaclav Kotesovec, May 29 2019 *)

Crossrefs

Cf. A005121, A260932.

For a signed version see A246040.

Sequence in context: A270529 A089155 A254530 * A246040 A183773 A247982

Adjacent sequences: A086552 A086553 A086554 * A086556 A086557 A086558

Keyword

nonn

Author

Vladeta Jovovic, Sep 14 2003

Status

approved