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A147144
Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 1000-1100-0110-0011 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 1, 1, 3, 3, 7, 7, 17, 17, 39, 39, 127, 127, 681, 681, 3913, 3913, 21369, 21369, 147701, 147701, 1344439, 1344439, 15252227
OFFSET
1,9
EXAMPLE
Maximal 9 X 9 example
.0.0.0.1.0.1.0.0.0
.0.0.1.1.0.1.1.0.0
.0.1.1.0.0.0.1.1.0
.1.1.0.0.0.0.0.1.1
.0.0.0.0.0.0.0.0.0
.1.1.0.0.0.0.0.1.1
.0.1.1.0.0.0.1.1.0
.0.0.1.1.0.1.1.0.0
.0.0.0.1.0.1.0.0.0
CROSSREFS
Sequence in context: A174583 A370202 A226781 * A152113 A146149 A263795
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved