A203279 Number of n X n binary arrays with every element neighboring horizontally or vertically both a 0 and a 1

0, 4, 28, 676, 72852, 26193924, 31747280900, 124891129720900, 1596519898829489564, 66137923505214401888644, 8881717991453403420376233852, 3865789910670398372168483012783044

Offset

1,2

Comments

Diagonal of A203285

Links

R. H. Hardin, Table of n, a(n) for n = 1..15

Example

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

Crossrefs

Sequence in context: A091969 A101346 A120604 * A081792 A336622 A354842

Adjacent sequences: A203276 A203277 A203278 * A203280 A203281 A203282

Keyword

nonn

Author

R. H. Hardin Dec 31 2011

Status

approved