A146798 - OEIS

A146798

Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 0110-0100-1111 pattern in any orientation.

1, 1, 1, 1, 1, 9, 49, 253, 1201, 4573, 30217, 286533, 2941009, 37746461, 678979449, 14880214645, 369497873441

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

OFFSET

1,6

LINKS

EXAMPLE

Maximal 8 X 8 example

.1.1.1.1.0.0.0.0

.0.1.0.0.0.0.0.1

.0.1.1.0.0.1.0.1

.1.0.0.0.0.1.1.1

.1.1.1.0.0.0.0.1

.1.0.1.0.0.1.1.0

.1.0.0.0.0.0.1.0

.0.0.0.0.1.1.1.1

CROSSREFS

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved