A190420 Number of (n+2)X(n+2) symmetric binary matrices without the pattern 1 1 1 diagonally or antidiagonally

44, 363, 6072, 191360, 10093200, 935338785, 154543989072, 44556415740672, 22668584136931568, 20377347136466565883, 32182451728510291871740, 89502269428191719999392640, 438593646987789744491801743584

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..17

Example

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

Crossrefs

Sequence in context: A183633 A200450 A024304 * A228464 A190605 A264555

Adjacent sequences: A190417 A190418 A190419 * A190421 A190422 A190423

Keyword

nonn

Author

R. H. Hardin May 10 2011

Status

approved