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.

A218186 Number of rows with the value true in the truth tables of all bracketed formulas with n distinct propositions p_1, ..., p_n connected by the binary connective of m-implication (case 1).

Original entry on oeis.org

0, 0, 1, 6, 37, 234, 1514, 9996, 67181, 458562, 3172478, 22206420, 157027938, 1120292388, 8055001716, 58314533400, 424740506109, 3110401363122, 22888001498102, 169155516667524, 1255072594261142, 9345400450314924, 69812926066668044, 523072984217339304, 3929809142578361938, 29598511892723647860
Offset: 0

Views

Author

N. J. A. Sloane, Oct 23 2012

Keywords

Crossrefs

Essentially the same as A025230.

Programs

  • PARI
    my(x='x+O('x^30)); concat([0,0], Vec((1-6*x-sqrt((1-4*x)*(1-8*x)))/2)) \\ Michel Marcus, Oct 21 2020

Formula

Yildiz gives a g.f.
G.f.: (1-6*x-sqrt((1-4*x)*(1-8*x)))/2. - Michel Marcus, Oct 21 2020
D-finite with recurrence n*a(n) +(n+5)*a(n-1) +(n+44)*a(n-2) +(n+331)*a(n-3) +10*(-902*n+3859)*a(n-4) +34720*(n-6)*a(n-5)=0. - R. J. Mathar, Nov 22 2023

Extensions

a(6) corrected by Georg Fischer, Jun 07 2021