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.

A354121 Expansion of e.g.f. 1/(1 - log(1 + x))^4.

Original entry on oeis.org

1, 4, 16, 68, 316, 1616, 9080, 55800, 373080, 2699520, 21035040, 175708320, 1566916320, 14862171840, 149429426880, 1587766126080, 17779538050560, 209295747832320, 2583920845209600, 33389139008678400, 450642388471395840, 6342869733912760320
Offset: 0

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Author

Seiichi Manyama, May 17 2022

Keywords

Comments

a(46) is negative. - Vaclav Kotesovec, Jun 04 2022
It appears that a(n) is negative for even n >= 46. - Felix Fröhlich, Jun 04 2022

Crossrefs

Programs

  • Mathematica
    Table[Sum[(k+3)! * StirlingS1[n,k], {k,0,n}]/6, {n,0,20}] (* Vaclav Kotesovec, Jun 04 2022 *)
  • PARI
    my(N=30, x='x+O('x^N)); Vec(serlaplace(1/(1-log(1+x))^4))
    
  • PARI
    a(n) = sum(k=0, n, (k+3)!*stirling(n, k, 1))/6;

Formula

a(n) = (1/6) * Sum_{k=0..n} (k + 3)! * Stirling1(n,k).
a(0) = 1; a(n) = Sum_{k=1..n} (-1)^(k-1) * (3 * k/n + 1) * (k-1)! * binomial(n,k) * a(n-k). - Seiichi Manyama, Nov 19 2023