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.

A105796 "Stirling-Bernoulli transform" of Jacobsthal numbers.

Original entry on oeis.org

0, 1, 1, 13, 25, 541, 1561, 47293, 181945, 7087261, 34082521, 1622632573, 9363855865, 526858348381, 3547114323481, 230283190977853, 1771884893993785, 130370767029135901, 1128511554418948441, 92801587319328411133, 892562598748128067705, 81124824998504073881821
Offset: 0

Views

Author

Paul Barry, Apr 20 2005

Keywords

Crossrefs

Cf. A050946.

Programs

  • Maple
    a:= n-> -add((-1)^k*k!*Stirling2(n+1, k+1)*(<<0|1>, <2|1>>^k)[1, 2], k=0..n):
    seq(a(n), n=0..23);  # Alois P. Heinz, May 09 2018
  • Mathematica
    CoefficientList[Series[E^x*(1-E^x)/((2-E^x)*(1-2*E^x)), {x, 0, 20}], x]* Range[0, 20]! (* Vaclav Kotesovec, Sep 26 2013 *)

Formula

E.g.f.: e^x*(1-e^x)/((2-e^x)*(1-2*e^x)).
a(n) = Sum_{k=0..n} (-1)^(n-k) * k! * S2(n,k) * A001045(k).
a(n) ~ n! * (2-(-1)^n)/(6*log(2)^(n+1)). - Vaclav Kotesovec, Sep 26 2013
a(n) = Sum_{k = 0..n} (-1)^(n-k)*A131689(n,k)*A001045(k). - Philippe Deléham, May 25 2015