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A147181
Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1000-1111-0101 pattern in any orientation.
0
1, 1, 1, 1, 1, 5, 17, 37, 129, 675, 4545, 33673, 284663, 3050875, 41150087, 686710451, 13852947253, 339116701643, 10235218350849, 379099740909573
OFFSET
1,6
EXAMPLE
Maximal 8 X 8 example
.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0
.0.0.0.0.1.0.0.0
.0.0.0.0.1.1.1.1
.0.0.1.1.0.1.0.1
.0.0.0.1.1.0.0.0
.0.0.0.1.0.0.0.0
.0.0.0.1.1.0.0.0
CROSSREFS
Sequence in context: A147219 A146280 A282511 * A146850 A146428 A146235
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved