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A147111
Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1000-1111-0010 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 1, 1, 3, 9, 19, 33, 77, 215, 619, 1943, 7543, 33395, 150047, 720261, 3747953, 21922241
OFFSET
1,9
EXAMPLE
Maximal 9 X 9 example
.0.0.0.0.1.1.1.0.0
.0.0.0.0.1.0.0.0.0
.0.0.0.1.1.0.0.0.1
.0.0.1.0.1.0.0.0.1
.1.1.1.1.0.1.1.1.1
.1.0.0.0.1.0.1.0.0
.1.0.0.0.1.1.0.0.0
.0.0.0.0.1.0.0.0.0
.0.0.1.1.1.0.0.0.0
CROSSREFS
Sequence in context: A146614 A146670 A146409 * A146401 A146465 A147119
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved