A293839 E.g.f.: exp(Sum_{n>=1} A000009(n)*x^n/n).

1, 1, 2, 8, 38, 238, 1828, 16096, 160604, 1826684, 23018264, 316422304, 4755059848, 77084268712, 1343682876272, 25097562397952, 498130253334032, 10479084018025744, 233353674153699616, 5470193826634531456, 134766983204541259616, 3482705318091355591136

Offset: 0

Author

Seiichi Manyama, Oct 17 2017

Keywords

• nonn

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..439

Crossrefs

Cf. A293840, A293841.

Cf. A215915.

Programs

Mathematica

nmax = 20; CoefficientList[Series[E^Sum[PartitionsQ[k]*x^k/k, {k, 1, nmax}], {x, 0, nmax}], x] * Range[0, nmax]! (* Vaclav Kotesovec, Oct 18 2017 *)

Formula

a(0) = 1 and a(n) = (n-1)! * Sum_{k=1..n} A000009(k)*a(n-k)/(n-k)! for n > 0.