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A146842
Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1001-1111-1000 pattern in any orientation.
0
1, 1, 1, 1, 1, 3, 13, 31, 85, 391, 2235, 16087, 124573, 1136363, 12958205, 185857105, 3266797811, 68594033643, 1733074438523, 53263262779599, 1999938243860711
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
.0.0.0.0.1.0.0.1
.0.0.0.0.1.1.1.1
.0.0.1.1.0.0.0.1
.0.0.0.1.0.0.0.0
.0.0.0.1.0.0.0.0
.0.0.1.1.1.0.0.0
CROSSREFS
Sequence in context: A146259 A146174 A147134 * A146191 A058264 A242905
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved