A146720 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1100-1111-1000 pattern in any orientation.

1, 1, 1, 1, 1, 1, 5, 17, 43, 65, 175, 507, 1901, 7015, 35249, 143079, 849399, 4342589, 31597665, 199056275, 1767268871

Offset

1,7

Links

Table of n, a(n) for n=1..21.

Example

Maximal 8 X 8 example
.1.1.1.0.0.0.1.1
.1.1.0.0.1.1.1.1
.0.1.0.0.0.0.0.1
.0.1.0.0.0.0.0.0
.0.0.0.0.0.0.1.0
.1.0.0.0.0.0.1.0
.1.1.1.1.0.0.1.1
.1.1.0.0.0.1.1.1

Crossrefs

Sequence in context: A055609 A231703 A265193 * A146640 A100705 A100662

Adjacent sequences: A146717 A146718 A146719 * A146721 A146722 A146723

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved