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A146921
Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 0110-1111-0110 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 1, 2, 4, 7, 11, 16, 35, 94, 264, 702, 1734, 4891, 17066, 67788, 281343, 1140052, 4839734, 23096235, 127115296, 766176694, 4824195749, 31420497455, 220872571333, 1715777826329
OFFSET
1,8
EXAMPLE
Maximal 8 X 8 example
.0.0.0.1.1.0.0.0
.0.0.1.1.1.1.0.0
.0.1.0.1.1.0.1.0
.1.1.1.0.0.1.1.1
.1.1.1.0.0.1.1.1
.0.1.0.1.1.0.1.0
.0.0.1.1.1.1.0.0
.0.0.0.1.1.0.0.0
CROSSREFS
Sequence in context: A120118 A108895 A146929 * A153535 A116615 A053145
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved