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A146837
Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1001-1111-0100 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 7, 15, 37, 79, 151, 497, 1751, 6209, 28231, 127833, 673629, 3604831, 23345419, 158561859, 1232306475
OFFSET
1,7
EXAMPLE
Maximal 8 X 8 example
.0.0.1.0.0.1.0.0
.0.0.1.1.1.1.0.0
.1.1.0.0.1.0.1.1
.0.1.1.0.0.0.1.0
.0.1.0.0.0.1.1.0
.1.1.0.1.0.0.1.1
.0.0.1.1.1.1.0.0
.0.0.1.0.0.1.0.0
CROSSREFS
Sequence in context: A063592 A159792 A247606 * A146044 A048694 A041094
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved