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.

A187652 Alternated binomial cumulative sums of the (signless) central Stirling numbers of the first kind (A187646).

Original entry on oeis.org

1, 0, 10, 194, 5932, 237624, 11820780, 702992968, 48662470640, 3843811669088, 341207224961856, 33627579102171680, 3643463136559851440, 430456189350273371648, 55075003474909952394848, 7586546772496980353804704
Offset: 0

Views

Author

Emanuele Munarini, Mar 12 2011

Keywords

Crossrefs

Cf. A187646.

Programs

  • Maple
    seq(sum((-1)^(n-k)*binomial(n,k)*abs(combinat[stirling1](2*k,k)),k=0..n),n=0..12);
  • Mathematica
    Table[Sum[(-1)^(n - k)Binomial[n, k]Abs[StirlingS1[2k, k]], {k, 0, n}], {n, 0, 15}]
  • Maxima
    makelist(sum((-1)^(n-k)*binomial(n,k)*abs(stirling1(2*k,k)),k,0,n),n,0,12);

Formula

a(n) = Sum_{k=0..n} (-1)^(n-k)*binomial(n,k)*abs(Stirling1(2*k,k)).
a(n) ~ c * d^n * (n-1)!, where d = 8*w^2/(2*w-1), where w = -LambertW(-1,-exp(-1/2)/2) = 1.7564312086261696769827376166... and c = exp((1-2*w)/(8*w^2)) / (2^(3/2)*Pi*sqrt(w-1)) = exp(-1/d) / (2^(3/2)*Pi*sqrt(w-1)) = 0.11686978539934159049334861225275481804523808136863346883911376048... - Vaclav Kotesovec, Jul 05 2021, updated May 25 2025