A147033 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 0100-0100-1111-0010 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 5, 31, 53, 91, 191, 751, 2485, 12125, 48629, 262319, 1174125, 7756611, 44436085, 360750867, 2552407571

Offset

1,8

Links

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

Example

Maximal 8 X 8 example
.0.0.1.0.0.1.0.0
.0.0.1.1.0.1.0.0
.1.1.1.0.1.1.1.1
.0.0.1.0.0.0.1.0
.0.1.0.0.0.1.0.0
.1.1.1.1.0.1.1.1
.0.0.1.0.1.1.0.0
.0.0.1.0.0.1.0.0

Crossrefs

Sequence in context: A130474 A238674 A245523 * A125743 A332788 A333243

Adjacent sequences: A147030 A147031 A147032 * A147034 A147035 A147036

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved