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.

A228284 Number of nX9 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or nw-se diagonally.

Original entry on oeis.org

34, 277, 9637, 186414, 4416695, 97268701, 2197847780, 49208639399, 1105411581741, 24801939723742, 556713719650007, 12494370307905104, 280426447918993931, 6293836975716291709, 141258681814255369288
Offset: 1

Views

Author

R. H. Hardin Aug 19 2013

Keywords

Comments

Column 9 of A228285

Examples

			Some solutions for n=4
..1..0..0..0..0..0..0..0..0....1..0..0..0..0..0..0..0..0
..0..0..0..1..0..0..1..0..0....0..0..0..1..0..0..1..0..0
..0..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0..0
..0..0..1..0..1..0..1..0..1....0..0..1..0..1..0..0..1..0
		

Crossrefs

See A228277-A228285, especially the latter.

Formula

Satisfies a recurrence of order 89 (see link above) - see Zeilberger links in A228285 for a proof that this is correct, and for a g.f.

Extensions

Edited by N. J. A. Sloane, Aug 22 2013