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.

Showing 1-2 of 2 results.

A362164 Expansion of e.g.f. -exp(x * (1-3*x)^(1/3)).

Original entry on oeis.org

-1, -1, 1, 11, 63, 499, 6089, 97551, 1875551, 41846183, 1062206289, 30214274419, 951599063711, 32864817109851, 1234766859596633, 50132215859126519, 2187063341006059839, 102022039514031274831, 5067161180856909388961, 266960634868753685833563
Offset: 0

Views

Author

Seiichi Manyama, Apr 10 2023

Keywords

Crossrefs

Programs

  • Mathematica
    With[{nn=20},CoefficientList[Series[-Exp[x*CubeRoot[1-3x]],{x,0,nn}],x] Range[0,nn]!] (* Harvey P. Dale, Mar 18 2025 *)
  • PARI
    my(N=20, x='x+O('x^N)); Vec(serlaplace(-exp(x*(1-3*x)^(1/3))))

Formula

a(n) = - n! * Sum_{k=0..n} (-3)^k * binomial((n-k)/3,k)/(n-k)!.

A362162 Expansion of e.g.f. exp(-x * (1-9*x)^(1/3)).

Original entry on oeis.org

1, -1, 7, 35, 1009, 30179, 1215631, 60016823, 3515979265, 238183128071, 18310183815511, 1574357806379819, 149678991229092337, 15588994684997694635, 1764907186597557771679, 215797860684193053430079, 28338759496501422888009601, 3977749154644186102350453263
Offset: 0

Views

Author

Seiichi Manyama, Apr 10 2023

Keywords

Crossrefs

Cf. A362159.

Programs

  • PARI
    my(N=20, x='x+O('x^N)); Vec(serlaplace(exp(-x*(1-9*x)^(1/3))))

Formula

a(n) = (-1)^n * n! * Sum_{k=0..n} 9^k * binomial((n-k)/3,k)/(n-k)!.
Showing 1-2 of 2 results.