A146182 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 110-111-100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 9, 9, 33, 33, 113, 113, 1711, 1711, 59971, 59971, 1694043, 1694043, 74822217, 74822217, 7821008273, 7821008273, 1319866139817, 1319866139817

Offset

1,7

Links

Table of n, a(n) for n=1..24.

Example

Maximal 8 X 8 example
.0.1.0.0.0.0.1.0
.1.1.0.0.0.0.1.1
.1.1.1.0.0.1.1.1
.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0
.1.1.1.0.0.1.1.1
.1.1.0.0.0.0.1.1
.0.1.0.0.0.0.1.0

Crossrefs

Sequence in context: A147117 A147263 A146234 * A147149 A147277 A146138

Adjacent sequences: A146179 A146180 A146181 * A146183 A146184 A146185

Keyword

nonn

Author

R. H. Hardin, Oct 27 2008

Status

approved