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A146673 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1100-0111-0110 pattern in any orientation. 0
1, 1, 1, 1, 1, 17, 51, 293, 1459, 7621, 56935, 702993, 8365419, 152139369, 2979251133 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

Maximal 8 X 8 example

.0.0.0.0.0.1.1.0

.0.1.0.0.1.1.1.0

.1.1.0.0.0.0.1.1

.1.1.1.0.0.1.0.0

.0.0.1.0.0.1.1.1

.1.1.0.0.0.0.1.1

.0.1.1.1.0.0.1.0

.0.1.1.0.0.0.0.0

CROSSREFS

Sequence in context: A214660 A258598 A223906 * A330390 A078757 A041560

Adjacent sequences:  A146670 A146671 A146672 * A146674 A146675 A146676

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified December 2 10:53 EST 2021. Contains 349440 sequences. (Running on oeis4.)