A146036 - OEIS

A146036

Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 3X3 el 1,1 1,2 1,3 2,3 3,3 in any orientation.

1, 1, 1, 1, 1, 1, 11, 17, 43, 77, 281, 645, 3017, 9213, 61533, 218977, 1561879, 6900617, 60762405, 333893691, 3718652761, 25349082469, 352708796463, 2947039725027

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

OFFSET

1,7

LINKS

Table of n, a(n) for n=1..24.

EXAMPLE

Maximal 8 X 8 example

.0.1.0.0.0.0.0.0

.0.1.0.0.0.1.1.1

.0.1.1.1.0.1.0.0

.0.0.0.0.0.1.0.0

.0.0.1.0.0.0.0.0

.0.0.1.0.1.1.1.0

.1.1.1.0.0.0.1.0

.0.0.0.0.0.0.1.0

CROSSREFS

Sequence in context: A187060 A190800 A191456 * A248482 A267772 A046122

Adjacent sequences: A146033 A146034 A146035 * A146037 A146038 A146039

KEYWORD

nonn

AUTHOR

R. H. Hardin, Oct 26 2008

STATUS

approved