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A146854
Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1100-1111-0001 pattern in any orientation.
0
1, 1, 1, 1, 5, 21, 55, 223, 1323, 7243, 56001, 498505, 5857355, 89335203, 1598206021, 35814813801
OFFSET
1,5
EXAMPLE
Maximal 8 X 8 example
.0.1.1.0.0.1.1.0
.0.0.1.0.0.0.1.0
.0.0.1.1.0.0.1.1
.0.0.1.1.0.0.1.1
.1.1.0.0.1.1.0.0
.1.1.0.0.1.1.0.0
.0.1.0.0.0.1.0.0
.0.1.1.0.0.1.1.0
CROSSREFS
Sequence in context: A096942 A365300 A122244 * A299120 A033275 A166464
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved