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A147138 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1000-1001-1111 pattern in any orientation. 0
1, 1, 1, 1, 9, 17, 47, 169, 947, 4301, 28001, 189379, 2123749, 21459731, 367346875, 5385601539 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..16.

EXAMPLE

Maximal 8 X 8 example

.0.0.0.0.1.1.1.1

.1.0.0.0.1.0.0.1

.1.0.0.1.0.0.0.1

.1.1.1.1.0.0.0.0

.0.0.0.0.1.1.1.1

.1.0.0.0.1.0.0.1

.1.0.0.1.0.0.0.1

.1.1.1.1.0.0.0.0

CROSSREFS

Sequence in context: A146625 A318755 A146576 * A282764 A319018 A101304

Adjacent sequences:  A147135 A147136 A147137 * A147139 A147140 A147141

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified August 18 13:25 EDT 2019. Contains 326100 sequences. (Running on oeis4.)