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.

A293995 Number of linear chord diagrams having n chords and no chord length larger than three.

Original entry on oeis.org

1, 1, 3, 15, 35, 103, 343, 979, 2915, 8935, 26559, 79499, 239547, 717455, 2151095, 6459027, 19371507, 58106071, 174349295, 523022555, 1569013931, 4707208351, 14121515303, 42364215075, 127093528675, 381280144743, 1143838446943, 3431519977579, 10294558387995
Offset: 0

Views

Author

Alois P. Heinz, Oct 21 2017

Keywords

Crossrefs

Column k=3 of A293960.

Programs

  • Mathematica
    LinearRecurrence[{2,1,8,-6},{1,1,3,15},30] (* Harvey P. Dale, Aug 08 2021 *)

Formula

G.f.: -(x-1)/((3*x-1)*(2*x^3-2*x^2-x-1)).