A147221 - OEIS

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A147221

Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1100-0111-0101 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 15, 37, 69, 139, 485, 1489

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

OFFSET

1,8

LINKS

Table of n, a(n) for n=1..13.

EXAMPLE

Maximal 8 X 8 example

.0.0.1.1.0.0.0.0

.0.0.1.0.1.1.0.0

.0.1.1.1.0.1.1.1

.0.1.0.0.0.1.0.1

.1.0.1.0.0.0.1.0

.1.1.1.0.1.1.1.0

.0.0.1.1.0.1.0.0

.0.0.0.0.1.1.0.0

CROSSREFS

Sequence in context: A181362 A082112 A059605 * A051461 A321383 A039605

Adjacent sequences: A147218 A147219 A147220 * A147222 A147223 A147224

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved