A202639 Number of (n+2) X (n+2) binary arrays avoiding patterns 000 and 111 in rows, columns and nw-to-se diagonals.

66, 530, 7432, 171362, 6324344, 386981422, 38841628112, 6372413856774, 1725107798449008, 768319633522920162

Offset

1,1

Comments

Diagonal of A202647.

Links

Table of n, a(n) for n=1..10.

Example

Some solutions for n=3
..1..0..1..0..0....1..1..0..1..0....1..0..0..1..0....0..0..1..1..0
..0..0..1..0..1....0..0..1..1..0....0..0..1..0..1....0..1..0..0..1
..0..1..0..1..1....0..1..0..0..1....0..1..0..1..1....1..1..0..1..1
..1..0..1..1..0....1..0..0..1..0....1..0..0..1..0....1..0..1..0..0
..0..0..1..0..1....0..1..1..0..0....0..1..1..0..0....0..1..0..0..1

Crossrefs

Cf. A202647.

Sequence in context: A063249 A106212 A155022 * A175260 A233065 A129218

Adjacent sequences: A202636 A202637 A202638 * A202640 A202641 A202642

Keyword

nonn

Author

R. H. Hardin, Dec 22 2011

Status

approved