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.

A209219 Number of n X n 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 0 and 1 1 1 vertically.

Original entry on oeis.org

2, 16, 60, 196, 900, 5476, 38232, 287296, 3132576, 37625956, 515992736, 9773299600, 197179936872, 5340055452736, 166631085360000, 6057724646680996, 305548384194976300, 15689243192533764624, 1137621414073872082528
Offset: 1

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Author

R. H. Hardin Mar 06 2012

Keywords

Comments

Diagonal of A209224

Examples

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