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.

A163989 First differences of A160379.

Original entry on oeis.org

1, 26, 8, 200, 26, 620, 56, 1304, 98, 2252, 152, 3464, 218, 4940, 296, 6680, 386, 8684, 488, 10952, 602, 13484, 728, 16280, 866, 19340, 1016, 22664, 1178, 26252, 1352, 30104, 1538, 34220, 1736, 38600, 1946, 43244, 2168, 48152, 2402, 53324, 2648, 58760, 2906
Offset: 1

Views

Author

Omar E. Pol, Sep 20 2009

Keywords

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{0,3,0,-3,0,1},{1,26,8,200,26,620,56,1304},50] (* Harvey P. Dale, May 19 2025 *)
  • PARI
    Vec(-x*(18*x^3+x^2+26*x+1)*(x^4+4*x^2+1)/((x-1)^3*(x+1)^3)  + O(x^100)) \\ Colin Barker, Sep 17 2013

Formula

a(2n+1) = 6n^2 + 2 for n>=1.
a(2n) = 132n^2 - 240n + 152 for n>=2.
From Colin Barker, Sep 17 2013: (Start)
a(n) = 3*a(n-2)-3*a(n-4)+a(n-6) for n>8.
G.f.: -x*(18*x^3+x^2+26*x+1)*(x^4+4*x^2+1) / ((x-1)^3*(x+1)^3). (End)

Extensions

Formula and more terms from Nathaniel Johnston, Nov 15 2010
More terms from Colin Barker, Sep 17 2013