A147018 - OEIS

A147018

Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 01000-11111-00010 pattern in any orientation.

1, 1, 1, 1, 5, 9, 21, 35, 177, 589, 4235, 15969, 164553, 879607, 12456629, 97189937, 1947709409, 20669429409

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

OFFSET

1,5

LINKS

EXAMPLE

Maximal 8 X 8 example

.0.1.0.0.0.0.1.0

.1.1.0.1.1.1.1.1

.0.1.0.0.1.0.0.0

.0.1.1.0.0.0.1.0

.0.1.0.0.0.1.1.0

.0.0.0.1.0.0.1.0

.1.1.1.1.1.0.1.1

.0.1.0.0.0.0.1.0

CROSSREFS

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved