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A147169 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1000-1101-0111 pattern in any orientation. 0
1, 1, 1, 1, 9, 21, 55, 201, 1193, 6291, 45811, 376085, 4555905 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

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

EXAMPLE

Maximal 8 X 8 example

.0.1.1.0.0.1.1.0

.0.1.0.0.0.0.1.1

.0.1.1.0.0.0.0.1

.0.0.1.1.0.0.1.1

.1.1.0.0.1.1.0.0

.1.0.0.0.0.1.1.0

.1.1.0.0.0.0.1.0

.0.1.1.0.0.1.1.0

CROSSREFS

Sequence in context: A176896 A134717 A216980 * A216167 A246327 A320896

Adjacent sequences:  A147166 A147167 A147168 * A147170 A147171 A147172

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified May 15 01:35 EDT 2021. Contains 343909 sequences. (Running on oeis4.)