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A147161 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1000-1100-0111-0100 pattern in any orientation. 0
1, 1, 1, 1, 1, 5, 25, 109, 547, 2673, 15771, 134989, 1264235 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

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

EXAMPLE

Maximal 8 X 8 example

.0.0.1.1.0.0.1.0

.1.1.1.0.0.0.1.0

.0.1.0.0.0.1.1.1

.0.1.0.0.1.1.0.0

.0.0.1.1.0.0.1.0

.1.1.1.0.0.0.1.0

.0.1.0.0.0.1.1.1

.0.1.0.0.1.1.0.0

CROSSREFS

Sequence in context: A272249 A275903 A273828 * A282077 A282085 A290920

Adjacent sequences:  A147158 A147159 A147160 * A147162 A147163 A147164

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified September 25 12:25 EDT 2021. Contains 347654 sequences. (Running on oeis4.)