A146833 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1001-1111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 17, 17, 49, 49, 317, 317, 3643, 3643, 63437, 63437, 1864637, 1864637, 68228177, 68228177

Offset

1,9

Links

Table of n, a(n) for n=1..22.

Example

Maximal 9 X 9 example
.0.0.0.0.0.0.0.0.0
.1.0.0.1.0.1.0.0.1
.1.1.1.1.0.1.1.1.1
.0.0.1.0.0.0.1.0.0
.0.0.0.0.0.0.0.0.0
.0.0.1.0.0.0.1.0.0
.1.1.1.1.0.1.1.1.1
.1.0.0.1.0.1.0.0.1
.0.0.0.0.0.0.0.0.0

Crossrefs

Sequence in context: A146588 A146628 A146636 * A146700 A146708 A146463

Adjacent sequences: A146830 A146831 A146832 * A146834 A146835 A146836

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved