A208374 Number of n X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 1 0 1 vertically.

2, 16, 72, 420, 2176, 10660, 60984, 340816, 1846240, 11076228, 66303360, 390426916, 2456007216, 15586002640, 98058552648, 645057461220, 4299810563584, 28563593727716, 195777751059000, 1361449965542992, 9468978890210480

Offset

1,1

Comments

Diagonal of A208379

Links

R. H. Hardin, Table of n, a(n) for n = 1..39

Example

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

Crossrefs

Sequence in context: A007758 A377714 A207874 * A207677 A207508 A208063

Adjacent sequences: A208371 A208372 A208373 * A208375 A208376 A208377

Keyword

nonn

Author

R. H. Hardin, Feb 25 2012

Status

approved