A146576 - OEIS

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A146576

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

1, 1, 1, 1, 1, 1, 9, 17, 45, 73, 207, 751, 2857, 11091, 59153, 255007, 1772283, 9573705, 76401883, 527044113, 5085713425, 43721092953

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

OFFSET

1,7

LINKS

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

EXAMPLE

Maximal 8 X 8 example

.0.0.0.0.0.0.1.0

.1.1.1.1.0.0.1.0

.0.0.1.0.1.1.1.0

.0.0.1.0.0.0.1.0

.0.1.0.0.0.1.0.0

.0.1.1.1.0.1.0.0

.0.1.0.0.1.1.1.1

.0.1.0.0.0.0.0.0

CROSSREFS

Sequence in context: A147245 A146625 A318755 * A147138 A282764 A319018

Adjacent sequences: A146573 A146574 A146575 * A146577 A146578 A146579

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved