A190422 Number of (n+2)X(n+2) symmetric binary matrices without the pattern 1 1 1 diagonally, vertically, antidiagonally or horizontally

34, 254, 3444, 76352, 2733816, 163925231, 16307921090, 2666369228454, 724501421348158, 326444188458835963, 242909750685458209759, 299419887986747081985221, 611366002048450741040107233

Offset

1,1

Links

Table of n, a(n) for n=1..13.

Example

Some solutions for n=2
..1..1..0..0....1..0..1..0....0..1..1..0....1..1..0..1....0..1..1..0
..1..1..0..0....0..0..0..1....1..0..1..0....1..1..0..1....1..0..0..0
..0..0..0..1....1..0..0..0....1..1..0..0....0..0..0..0....1..0..0..1
..0..0..1..0....0..1..0..1....0..0..0..0....1..1..0..0....0..0..1..0

Crossrefs

Sequence in context: A020872 A302474 A183319 * A209951 A209944 A371403

Adjacent sequences: A190419 A190420 A190421 * A190423 A190424 A190425

Keyword

nonn

Author

R. H. Hardin May 10 2011

Status

approved