A147288 - OEIS

A147288

Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1100-0111-0001-0001 pattern in any orientation.

1, 1, 1, 1, 5, 13, 29, 101, 617, 3357, 20865, 140793, 1290919, 15614005, 229745285, 3898534669

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

OFFSET

1,5

LINKS

EXAMPLE

Maximal 8 X 8 example

.1.0.0.1.1.1.0.0

.1.0.0.0.0.1.0.0

.1.1.1.0.0.1.1.0

.0.0.1.1.0.0.1.0

.0.1.0.0.1.1.0.0

.0.1.1.0.0.1.1.1

.0.0.1.0.0.0.0.1

.0.0.1.1.1.0.0.1

CROSSREFS

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved