A146824 - OEIS

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

(list; graph; refs; listen; history; text; internal format)

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

.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

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