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A146266
Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 110-111-110 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 10, 5, 44, 17, 490, 45, 3832, 281, 72349, 4672, 1945156, 78267, 77811492, 1571678, 4162726786, 52679419, 355835905036, 3071977536, 44996289731531, 240721783237
OFFSET
1,7
EXAMPLE
Maximal 8 X 8 example
.1.1.0.0.0.0.1.1
.1.1.1.0.0.1.1.1
.1.1.0.0.0.0.1.1
.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0
.1.1.0.0.0.0.1.1
.1.1.1.0.0.1.1.1
.1.1.0.0.0.0.1.1
CROSSREFS
Sequence in context: A361671 A183132 A141321 * A146218 A033962 A241360
KEYWORD
nonn
AUTHOR
STATUS
approved