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A146787
Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 0100-1100-1111 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 3, 5, 11, 21, 39, 105, 351, 1205, 4629, 16631, 70563, 335933, 1961161, 12194507, 84627809, 599408761
OFFSET
1,7
EXAMPLE
Maximal 8 X 8 example
.0.0.0.1.1.1.1.0
.0.0.0.1.1.0.0.1
.0.0.0.0.1.0.0.1
.1.1.0.0.0.1.1.1
.1.1.1.0.0.0.1.1
.1.0.0.1.0.0.0.0
.1.0.0.1.1.0.0.0
.0.1.1.1.1.0.0.0
CROSSREFS
Sequence in context: A298342 A293317 A230097 * A147243 A372451 A192664
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved