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.

A107293 The (1,1)-entry of the matrix M^n, where M is the 5 X 5 matrix [[0,1,0,0,0],[0,0,1,0,0], [0,0,0,1,0], [0,0,0,0,1], [1,0,-1,1,1]].

Original entry on oeis.org

0, 0, 0, 0, 1, 1, 2, 2, 3, 4, 6, 9, 13, 19, 27, 39, 56, 81, 117, 169, 244, 352, 508, 733, 1058, 1527, 2204, 3181, 4591, 6626, 9563, 13802, 19920, 28750, 41494, 59887, 86433, 124746, 180042, 259849, 375032, 541272, 781201, 1127483, 1627261, 2348575
Offset: 0

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Author

Roger L. Bagula, Jun 08 2005

Keywords

Comments

Also the (1,2)-entries of M^n (n >= 1).
Characteristic polynomial of the matrix M is x^5 - x^4 - x^3 + x^2 - 1.

Programs

  • Magma
    I:=[0,0,0,0,1]; [n le 5 select I[n] else Self(n-1) +Self(n-2) -Self(n-3) + Self(n-5): n in [1..50]]; // G. C. Greubel, Nov 03 2018
  • Maple
    a[0]:=0:a[1]:=0:a[2]:=0:a[3]:=0:a[4]:=1: for n from 5 to 45 do a[n]:=a[n-1]+a[n-2]-a[n-3]+a[n-5] od: seq(a[n],n=0..45);
  • Mathematica
    LinearRecurrence[{1,1,-1,0,1}, {0,0,0,0,1}, 50] (* G. C. Greubel, Nov 03 2018 *)
  • PARI
    m=50; v=concat([0,0,0,0,1], vector(m-5)); for(n=6, m, v[n] = v[n-1] +v[n-2] -v[n-3] +v[n-5]); v \\ G. C. Greubel, Nov 03 2018
    

Formula

a(n) = a(n-1) + a(n-2) - a(n-3) + a(n-5) for n >= 5.
O.g.f: x^4/(1 - x - x^2 + x^3 - x^5). - R. J. Mathar, Dec 02 2007

Extensions

Edited by N. J. A. Sloane, May 12 2006