A147120 - OEIS

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A147120

Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 1000-1000-1111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 3, 11, 11, 27, 27, 63, 63, 285, 285

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

OFFSET

1,13

LINKS

Table of n, a(n) for n=1..22.

EXAMPLE

Maximal 13 X 13 example

.0.0.0.0.1.0.0.0.1.0.0.0.0

.0.0.1.1.1.1.0.1.1.1.1.0.0

.0.1.0.0.0.1.0.1.0.0.0.1.0

.1.1.0.0.0.0.0.0.0.0.0.1.1

.0.1.1.1.0.0.0.0.0.1.1.1.0

.0.0.0.0.0.0.0.0.0.0.0.0.0

.0.1.1.1.0.0.0.0.0.1.1.1.0

.1.1.0.0.0.0.0.0.0.0.0.1.1

.0.1.0.0.0.1.0.1.0.0.0.1.0

.0.0.1.1.1.1.0.1.1.1.1.0.0

.0.0.0.0.1.0.0.0.1.0.0.0.0

CROSSREFS

Sequence in context: A068594 A147175 A147112 * A147159 A146828 A146583

Adjacent sequences: A147117 A147118 A147119 * A147121 A147122 A147123

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved