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.

A246578 Expansion of g.f. (Product_{r>=1} (1 - x^r))*x^(k^2)/Product_{i=1..k} ((1-x^i)^2) with k=4.

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 3, 5, 5, 7, 7, 8, 6, 5, 1, -2, -9, -15, -23, -30, -39, -46, -52, -56, -58, -57, -51, -43, -29, -13, 10, 33, 63, 90, 124, 152, 184, 207, 233, 245, 258, 255, 250, 227, 202, 157, 110, 45, -22, -104, -185, -278, -366
Offset: 0

Views

Author

N. J. A. Sloane, Aug 31 2014

Keywords

Crossrefs

k=0 gives A010815. Cf. A246575-A246578.

Programs

  • Maple
    fGL:=proc(k) local a,i,r;
    a:=x^(k^2)/mul((1-x^i)^2,i=1..k);
    a:=a*mul(1-x^r,r=1..101);
    series(a,x,101);
    seriestolist(%);
    end;fGL(4);
  • Mathematica
    With[{k = 4}, CoefficientList[Product[(1-x^r), {r, 1, nmax}]* x^(k^2)/Product[(1-x^i)^2, {i, 1, k}] + O[x]^nmax, x]] (* Jean-François Alcover, Mar 09 2023 *)