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A146878
Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1110-0100-0111 pattern in any orientation.
0
1, 1, 1, 1, 1, 9, 41, 249, 1137, 4177, 27849, 254297, 2360945, 31718257, 561884345, 12949529033, 316511614977
OFFSET
1,6
EXAMPLE
Maximal 8 X 8 example
.0.0.0.0.0.1.0.0
.1.1.1.0.0.1.1.1
.0.1.0.0.0.1.0.1
.0.1.1.1.0.0.0.1
.1.0.0.0.1.1.1.0
.1.0.1.0.0.0.1.0
.1.1.1.0.0.1.1.1
.0.0.1.0.0.0.0.0
CROSSREFS
Sequence in context: A171422 A129793 A304361 * A177259 A247884 A301803
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved