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A147274 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1000-1000-1111-0001 pattern in any orientation. 0
1, 1, 1, 1, 1, 5, 25, 85, 377, 1825, 10067, 61143 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

Table of n, a(n) for n=1..12.

EXAMPLE

Maximal 8 X 8 example

.0.0.0.1.0.0.1.1

.1.1.1.1.0.0.1.0

.1.0.0.0.0.0.1.0

.1.0.0.0.1.1.1.0

.0.1.1.1.0.0.0.1

.0.1.0.0.0.0.0.1

.0.1.0.0.1.1.1.1

.1.1.0.0.1.0.0.0

CROSSREFS

Sequence in context: A058919 A018212 A181477 * A147034 A146460 A223840

Adjacent sequences:  A147271 A147272 A147273 * A147275 A147276 A147277

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified December 15 14:37 EST 2019. Contains 329999 sequences. (Running on oeis4.)