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A147127
Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1000-1111-1000 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 1, 1, 3, 7, 15, 27, 51, 137, 397, 1327, 4515, 15837, 61007, 262125, 1291801
OFFSET
1,9
EXAMPLE
Maximal 9 X 9 example
.0.0.0.1.1.1.1.0.0
.0.0.0.0.1.0.0.0.0
.0.0.0.0.1.0.0.0.1
.1.0.0.0.1.0.0.0.1
.1.1.1.1.0.1.1.1.1
.1.0.0.0.1.0.0.0.1
.1.0.0.0.1.0.0.0.0
.0.0.0.0.1.0.0.0.0
.0.0.1.1.1.1.0.0.0
CROSSREFS
Sequence in context: A146425 A147595 A378278 * A146726 A146228 A139806
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved