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A147026
Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 01000-11111-01000 pattern in any orientation.
0
1, 1, 1, 1, 1, 9, 17, 35, 145, 589, 2723, 16121, 110705, 888953, 8435682, 98480917, 1294018001, 21003172843
OFFSET
1,6
EXAMPLE
Maximal 8 X 8 example
.0.1.0.0.1.0.0.0
.0.1.0.1.1.1.1.1
.0.1.0.0.1.0.0.0
.1.1.1.0.0.0.1.0
.0.1.0.0.0.1.1.1
.0.0.0.1.0.0.1.0
.1.1.1.1.1.0.1.0
.0.0.0.1.0.0.1.0
CROSSREFS
Sequence in context: A147279 A173788 A097478 * A055393 A147082 A145941
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved