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.

Showing 1-2 of 2 results.

A362576 Number of vertex cuts in the n X n rook complement graph.

Original entry on oeis.org

0, 9, 114, 908, 5985, 35505, 196602, 1036992, 5277357, 26134385, 126677826, 603492444, 2834183937, 13150592889, 60391598610, 274863240992, 1241212143357, 5566202141193, 24807561785514, 109950785325900, 484883791129185, 2128652665933409, 9306262365861834
Offset: 1

Views

Author

Eric W. Weisstein, Apr 25 2023

Keywords

Crossrefs

Formula

From Andrew Howroyd, Apr 30 2023: (Start)
a(n) = 2*n*(2^n-n-1) + n^2*(2^(n-1)-1)^2 + binomial(n,2)^2.
a(n) = 2^(n^2) - 1 - A291593(n). (End)

Extensions

a(2) corrected and terms a(6) and beyond from Andrew Howroyd, Apr 30 2023

A290949 Number of connected dominating sets in the n X n rook complement graph.

Original entry on oeis.org

1, 0, 325, 63899, 33542996, 68719407048, 562949953031061, 18446744073707483871, 2417851639229258338870480, 1267650600228229401496650962840, 2658455991569831745807614120307387245, 22300745198530623141535718272648360299106443
Offset: 1

Views

Author

Eric W. Weisstein, Sep 14 2017

Keywords

Crossrefs

Programs

  • Mathematica
    Table[If[n == 1, 1, 2^(n^2) - 2 n (2^n - 1) + n^2 (1 - 2 (2^(n - 1) - 1)^2 + (n - 1)^2) - 3 Binomial[n, 2]^2 - 1], {n, 20}] (* Eric W. Weisstein, Jan 15 2018 *)
  • PARI
    a(n) = if(n==1, 1, 2^(n^2) - 2*n*(2^n - 1) + n^2 - 2*n^2*(2^(n-1)-1)^2 + n^2*(n-1)^2 - 3*binomial(n,2)^2 - 1); \\ Andrew Howroyd, Jan 14 2018

Formula

a(n) = 2^(n^2) - 2*n*(2^n - 1) + n^2 - 2*n^2*(2^(n-1)-1)^2 + n^2*(n-1)^2 - 3*binomial(n,2)^2 - 1 for n > 1. - Andrew Howroyd, Jan 14 2018

Extensions

a(6)-a(12) from Andrew Howroyd, Jan 14 2018
Showing 1-2 of 2 results.