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.

A145150 8th column of A145142.

Original entry on oeis.org

1, 36, 870, 18150, 369303, 7698834, 166748153, 3751722975, 87886591793, 2152001539688, 55209634265136, 1483339949950248, 41681455251697936, 1223731327819009800, 37510006764224474480, 1199164490827755488960
Offset: 9

Views

Author

Alois P. Heinz, Oct 03 2008

Keywords

Crossrefs

Cf. A145153.

Programs

  • Maple
    row:= proc(n) option remember; local f,i,x; f:= unapply (simplify (sum ('cat (a||i) *x^i', 'i'=0..n-1) ), x); unapply (subs (solve ({seq(f(i+1)= coeftayl (x/ (1-x-x^4)/ (1-x)^i, x=0, n), i=0..n-1)}, {seq (cat (a||i), i=0..n-1)}), sum ('cat (a||i) *x^i', 'i'=0..n-1) ), x); end: a:= n-> `if` (n=0, 0, coeftayl (row(n)(x), x=0, 8) *(n-1)!): seq (a(n), n=9..26);
  • Mathematica
    row[n_] := row[n] = Module[{f, a, eq}, f = Function[x, Sum[a[k]*x^k, {k, 0, n-1}]]; eq = Table[f[k+1] == SeriesCoefficient[x/(1-x-x^4)/(1-x)^k, {x, 0, n}], {k, 0, n-1}]; List @@ f[1] /. Solve[eq] // First]; a[n_] := row[n][[9]]*(n-1)!; Table[a[n], {n, 9, 26}] (* Jean-François Alcover, Feb 14 2014, after Maple *)