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A146597
Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1000-1000-1111 pattern in any orientation.
0
1, 1, 1, 1, 3, 7, 19, 51, 237, 1335, 8829, 68891, 649429, 7839465, 116522409, 2129542541, 47609599737, 1308687213295, 44429361526611, 1853713445956347
OFFSET
1,5
EXAMPLE
Maximal 8 X 8 example
.0.1.1.1.1.0.0.0
.1.0.0.0.1.0.0.0
.1.0.0.0.1.0.0.0
.1.0.0.0.0.1.1.1
.1.1.1.0.0.0.0.1
.0.0.0.1.0.0.0.1
.0.0.0.1.0.0.0.1
.0.0.0.1.1.1.1.0
CROSSREFS
Sequence in context: A087432 A135052 A198305 * A320734 A259812 A115254
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved