A146809 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1010-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 17, 17, 65, 65, 349, 349, 3731, 3731, 77219, 77219, 2029815, 2029815, 63522619, 63522619

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
.0.0.0.1.0.1.0.0.0
.0.1.0.1.0.1.0.1.0
.1.1.1.1.0.1.1.1.1
.0.0.0.0.0.0.0.0.0
.1.1.1.1.0.1.1.1.1
.0.1.0.1.0.1.0.1.0
.0.0.0.1.0.1.0.0.0
.0.0.0.0.0.0.0.0.0

Crossrefs

Sequence in context: A146580 A146455 A146048 * A147233 A146817 A146660

Adjacent sequences: A146806 A146807 A146808 * A146810 A146811 A146812

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved