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A146615
Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 1000-1111-0110 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 7, 7, 21, 21, 49, 49, 235, 235, 1289, 1289, 9339
OFFSET
1,13
EXAMPLE
Maximal 13 X 13 example
.0.0.0.0.0.1.0.1.0.0.0.0.0
.0.0.1.1.1.1.0.1.1.1.1.0.0
.0.1.0.1.1.0.0.0.1.1.0.1.0
.0.1.1.0.0.0.0.0.0.0.1.1.0
.0.1.1.0.0.0.0.0.0.0.1.1.0
.1.1.0.0.0.0.0.0.0.0.0.1.1
.0.0.0.0.0.0.0.0.0.0.0.0.0
.1.1.0.0.0.0.0.0.0.0.0.1.1
.0.1.1.0.0.0.0.0.0.0.1.1.0
.0.1.1.0.0.0.0.0.0.0.1.1.0
.0.1.0.1.1.0.0.0.1.1.0.1.0
.0.0.1.1.1.1.0.1.1.1.1.0.0
.0.0.0.0.0.1.0.1.0.0.0.0.0
CROSSREFS
Sequence in context: A146671 A146639 A146703 * A146735 A146711 A146402
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
EXTENSIONS
Example repaired. - R. H. Hardin, Nov 05 2008
STATUS
approved