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A146638
Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1010-1111-0100 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 1, 3, 9, 19, 33, 57, 181, 727, 3143, 12709, 46177, 203713, 1168453, 7869343, 57494841, 429662591, 3357500475
OFFSET
1,8
EXAMPLE
Maximal 8 X 8 example
.0.0.0.1.0.1.0.0
.0.0.1.1.1.1.0.0
.0.1.0.0.1.0.1.1
.1.1.0.0.0.1.1.0
.0.1.1.0.0.0.1.1
.1.1.0.1.0.0.1.0
.0.0.1.1.1.1.0.0
.0.0.1.0.1.0.0.0
CROSSREFS
Sequence in context: A328950 A049749 A147055 * A147135 A146843 A146630
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved