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A147212
Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1100-0111-0011 pattern in any orientation.
0
1, 1, 1, 1, 3, 9, 23, 55, 315, 2117, 14227, 107639, 1242577, 18337443, 306941589, 6236872411, 166949397689, 5617277183949, 229023263912585, 11581498844555427
OFFSET
1,5
EXAMPLE
Maximal 8 X 8 example
.0.0.0.0.1.1.0.0
.0.0.0.0.0.1.1.1
.0.0.0.0.0.0.1.1
.0.0.0.0.1.1.0.0
.1.0.0.1.0.1.1.1
.1.1.0.1.1.0.1.1
.0.1.1.0.1.1.0.0
.0.1.1.0.1.1.0.0
CROSSREFS
Sequence in context: A305168 A274099 A147126 * A341029 A045883 A292329
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved