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A146640
Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1010-1111-0100 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 5, 17, 43, 75, 161, 539, 2129, 8565, 42667, 183445, 1039641, 5959305, 43560487, 311334093, 2752013037
OFFSET
1,7
EXAMPLE
Maximal 8 X 8 example
.0.1.0.0.1.0.1.0
.1.1.0.0.1.1.1.1
.0.1.1.0.0.1.0.0
.1.1.0.0.0.0.0.0
.0.0.0.0.0.0.1.1
.0.0.1.0.0.1.1.0
.1.1.1.1.0.0.1.1
.0.1.0.1.0.0.1.0
CROSSREFS
Sequence in context: A231703 A265193 A146720 * A100705 A100662 A168617
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved