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A146649
Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1010-1111-1000 pattern in any orientation.
0
1, 1, 1, 1, 5, 25, 55, 257, 1343, 7017, 52361, 533979, 5651335, 90178433, 1487870527, 34319557235, 869941319597
OFFSET
1,5
EXAMPLE
Maximal 8 X 8 example
.0.1.1.1.0.1.1.1
.0.0.1.0.0.0.1.0
.0.0.1.1.0.0.1.1
.0.0.1.0.0.0.1.0
.0.1.0.0.0.1.0.0
.1.1.0.0.1.1.0.0
.0.1.0.0.0.1.0.0
.1.1.1.0.1.1.1.0
CROSSREFS
Sequence in context: A044082 A161143 A045576 * A326314 A273357 A146412
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved