A147145 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1000-1100-0110-0011 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 13, 25, 51, 161, 489, 1381, 4593, 16307, 70385

Offset

1,9

Links

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

Example

Maximal 9 X 9 example
.1.0.0.0.0.0.0.1.1
.1.1.0.0.0.0.1.1.0
.0.1.1.0.0.1.1.0.0
.0.0.1.1.0.1.0.0.0
.0.0.0.0.0.0.0.0.0
.0.0.0.1.0.1.1.0.0
.0.0.1.1.0.0.1.1.0
.0.1.1.0.0.0.0.1.1
.1.1.0.0.0.0.0.0.1

Crossrefs

Sequence in context: A277714 A163551 A005696 * A283174 A298037 A283255

Adjacent sequences: A147142 A147143 A147144 * A147146 A147147 A147148

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved