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.

A264237 Sum of values of vertices at level n of the hyperbolic Pascal pyramid.

Original entry on oeis.org

1, 3, 9, 33, 165, 1137, 9837, 95193, 962541, 9884889, 102049197, 1055383929, 10921055661, 113032307769, 1169952636525, 12109971475065, 125349031354029, 1297477519769145, 13430093334225645, 139013932289379321, 1438923355509080877, 14894194022848480185
Offset: 0

Views

Author

Michel Marcus, Nov 09 2015

Keywords

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[-(20*x^5 - 8*x^4 + 58*x^3 - 54*x^2 + 15*x - 1)/((x - 1)*(2*x^2 - 4*x + 1)*(6*x^3 - 28*x^2 + 13*x - 1)), {x, 0, 20}], x] (* Wesley Ivan Hurt, Sep 17 2017 *)
  • PARI
    Vec(-(20*x^5-8*x^4+58*x^3-54*x^2+15*x-1)/((x-1)*(2*x^2-4*x+1)*(6*x^3-28*x^2+13*x-1)) + O(x^30)) \\ Colin Barker, Nov 09 2015

Formula

a(n) = 18*a(n-1) - 99*a(n-2) + 226*a(n-3) - 224*a(n-4) + 92*a(n-5) - 12*a(n-6), for n >= 7.
G.f.: -(20*x^5-8*x^4+58*x^3-54*x^2+15*x-1) / ((x-1)*(2*x^2-4*x+1)*(6*x^3-28*x^2+13*x-1)). - Colin Barker, Nov 09 2015

Extensions

Definition edited by Eric M. Schmidt, Sep 17 2017