A146661 - OEIS

A146661

Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1100-0111-0001 pattern in any orientation.

1, 1, 1, 1, 3, 9, 23, 67, 379, 2563, 18843, 171357, 2142397, 34085501, 656314291, 15909337201, 492190457043, 19216875516479, 939930272232161

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

OFFSET

1,5

LINKS

EXAMPLE

Maximal 8 X 8 example

.0.0.1.1.0.0.0.0

.0.0.0.1.0.0.0.1

.1.0.0.1.1.0.1.1

.1.1.1.0.1.0.1.0

.0.0.1.1.0.1.1.0

.0.0.0.0.1.0.0.0

.0.0.1.1.1.0.0.0

.0.1.1.0.0.0.0.0

CROSSREFS

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved