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A145971
Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a one by five or five by one block.
0
1, 1, 1, 1, 9, 9, 54, 93, 747, 1903, 18738, 80363, 1083847, 6706491, 120203159, 1028058854
OFFSET
1,5
EXAMPLE
Maximal 8 X 8 example
.1.1.1.1.1.0.0.1
.0.0.0.0.0.0.0.1
.0.1.1.1.1.1.0.1
.1.0.0.0.0.0.0.1
.1.0.0.0.0.0.0.1
.1.0.1.1.1.1.1.0
.1.0.0.0.0.0.0.0
.1.0.0.1.1.1.1.1
CROSSREFS
Sequence in context: A014718 A371374 A339324 * A241868 A243125 A270008
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 25 2008
STATUS
approved