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A146645
Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1010-1111-1000 pattern in any orientation.
0
1, 1, 1, 1, 1, 5, 17, 39, 143, 759, 4705, 36573, 332389, 3601255, 48371515, 827745175, 17238229681, 441854255629, 13777843130457, 527986032874649, 24769703202602783
OFFSET
1,6
EXAMPLE
Maximal 8 X 8 example
.0.0.0.1.1.1.0.0
.0.0.0.0.1.0.1.0
.0.0.0.1.1.0.1.1
.1.0.1.0.1.0.1.0
.1.1.1.1.0.1.1.1
.1.0.0.0.1.0.0.0
.0.1.1.1.1.0.0.0
.0.0.1.0.1.0.0.0
CROSSREFS
Sequence in context: A163686 A147165 A147257 * A146717 A147467 A146272
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved