A146824 Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 1000-1111-0100-0100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 193, 369, 2631, 6147, 72935, 183013, 4104827, 12415887, 1843421399, 7169739931, 1106512780955, 5150025315155, 883358137678737, 4992528269858869

Offset

1,9

Links

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

Example

Maximal 9 X 9 example
.0.0.1.0.0.0.1.0.0
.0.0.1.0.0.0.1.0.0
.1.1.1.1.0.1.1.1.1
.0.0.0.1.0.1.0.0.0
.0.0.0.0.0.0.0.0.0
.0.0.0.1.0.1.0.0.0
.1.1.1.1.0.1.1.1.1
.0.0.1.0.0.0.1.0.0
.0.0.1.0.0.0.1.0.0

Crossrefs

Sequence in context: A139506 A342308 A147171 * A256348 A142453 A065213

Adjacent sequences: A146821 A146822 A146823 * A146825 A146826 A146827

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved