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A147039
Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 0100-0100-1111-0100 pattern in any orientation.
0
1, 1, 1, 1, 1, 3, 5, 9, 21, 37, 87, 219, 581, 2019, 6603, 23569, 95313
OFFSET
1,6
EXAMPLE
Maximal 8 X 8 example
.0.1.0.0.0.1.0.0
.1.1.1.1.0.1.0.0
.0.1.0.0.1.1.1.1
.0.1.0.0.0.1.0.0
.0.0.1.0.0.0.1.0
.1.1.1.1.0.0.1.0
.0.0.1.0.1.1.1.1
.0.0.1.0.0.0.1.0
CROSSREFS
Sequence in context: A065901 A053662 A050355 * A069927 A136401 A147758
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved