A190604 Number of (n+2)X(n+2) symmetric binary matrices without the pattern 1 0 1 diagonally

56, 672, 14112, 522144, 33939360, 3869087040, 773817408000, 271609910208000, 167311704688128000, 180863952767866368000, 343098918400642500096000, 1142176299355738882819584000, 6672593940836226553432009728000

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..62

Example

Some solutions for 4X4
..1..1..1..0....0..0..1..0....1..0..1..0....0..1..1..0....1..1..1..1
..1..0..1..1....0..0..0..1....0..1..1..1....1..0..1..0....1..0..1..0
..1..1..0..1....1..0..1..1....1..1..1..0....1..1..1..0....1..1..0..1
..0..1..1..0....0..1..1..0....0..1..0..0....0..0..0..0....1..0..1..1

Crossrefs

Sequence in context: A027813 A199914 A190535 * A136006 A138410 A240269

Adjacent sequences: A190601 A190602 A190603 * A190605 A190606 A190607

Keyword

nonn

Author

R. H. Hardin May 13 2011

Status

approved