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A146660
Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1100-0111-0001 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 1, 1, 17, 17, 73, 73, 521, 521, 7411, 7411, 207693, 207693, 7583663, 7583663, 399906057, 399906057
OFFSET
1,9
EXAMPLE
Maximal 9 X 9 example
.0.0.0.0.0.0.0.0.0
.1.0.0.0.0.0.0.0.1
.1.1.1.0.0.0.1.1.1
.0.0.1.1.0.1.1.0.0
.0.0.0.0.0.0.0.0.0
.0.0.1.1.0.1.1.0.0
.1.1.1.0.0.0.1.1.1
.1.0.0.0.0.0.0.0.1
.0.0.0.0.0.0.0.0.0
CROSSREFS
Sequence in context: A146809 A147233 A146817 * A070852 A146596 A146391
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved