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.

A144639 Column 4 of triangle in A144633.

Original entry on oeis.org

0, 0, 0, 0, 1, -10, 85, -700, 5565, -39270, 163625, 2002000, -80455375, 1796144350, -33225267075, 532997965500, -6863056074875, 39757008541250, 1589961504756625, -87655679826715000, 2971557080832965625, -82299265240798856250, 1913986621864144953125
Offset: 0

Views

Author

N. J. A. Sloane, Jan 23 2009

Keywords

Programs

  • Maple
    A:= proc(n, k) option remember; if n=k then 1 elif k A(i-1, j-1))^(-1) end: a:= n-> M(n+4)[5, n+1]: seq(a(n), n=0..25);  # Alois P. Heinz, Oct 25 2009
  • Mathematica
    max = 30; t[n_, n_] = 1; t[n_ /; n >= 0, k_] /; (0 <= k <= 3*n) := t[n, k] = t[n-1, k-1]+(k-1)*t[n-1, k-2]+(1/2)*(k-1)*(k-2)*t[n-1, k-3]; t[, ] = 0; A144633 = Table[t[n, k], {n, 0, max}, {k, 0, max}] // Inverse // Transpose; a[n_] := A144633[[n+1, 5]]; Table[a[n], {n, 0, max}] (* Jean-François Alcover, Mar 19 2014 *)

Formula

E.g.f.: B(x)^4/24 where B(x) is e.g.f. for A144636. - Vladeta Jovovic, Jan 24 2009

Extensions

More terms from Alois P. Heinz, Oct 25 2009