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A146822
Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1000-1110-0111 pattern in any orientation.
0
1, 1, 1, 1, 5, 21, 63, 331, 1837, 11817, 91941, 951301, 13059325, 223458589, 4681971763
OFFSET
1,5
EXAMPLE
Maximal 8 X 8 example
.1.0.1.1.0.1.1.0
.1.1.0.1.1.0.1.1
.1.1.0.1.1.0.1.1
.0.1.1.0.1.0.0.1
.1.0.0.1.0.1.1.0
.1.1.0.1.1.0.1.1
.1.1.0.1.1.0.1.1
.0.1.1.0.1.1.0.1
CROSSREFS
Sequence in context: A196631 A357723 A342379 * A146223 A181093 A055384
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved