cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A380309 Expansion of e.g.f. exp( 1 - 1/(1-3*x)^(1/3) ).

Original entry on oeis.org

1, -1, -3, -17, -143, -1601, -22419, -377217, -7415743, -166854657, -4229195779, -119251176881, -3702809175823, -125546570425537, -4615357640315603, -182855338776726561, -7766868454872857599, -352082642456714366977, -16965451818345573907843
Offset: 0

Views

Author

Seiichi Manyama, Jan 20 2025

Keywords

Crossrefs

Programs

  • PARI
    my(N=20, x='x+O('x^N)); Vec(serlaplace(exp(1-1/(1-3*x)^(1/3))))

Formula

a(n) = Sum_{k=0..n} 3^(n-k) * |Stirling1(n,k)| * A000587(k).
a(n) = e * (-3)^n * n! * Sum_{k>=0} (-1)^k * binomial(-k/3,n)/k!.
a(0) = 1; a(n) = -Sum_{k=1..n} A007559(k) * binomial(n-1,k-1) * a(n-k).