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A146834
Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1001-1111-0100 pattern in any orientation.
0
1, 1, 1, 1, 1, 5, 17, 41, 159, 789, 4693, 37959, 362149, 3798435, 51198703, 878343647, 18110228679, 463058495339, 14563433819389, 553118211838649, 25843199757659397
OFFSET
1,6
EXAMPLE
Maximal 8 X 8 example
.0.0.1.0.0.1.0.0
.0.0.1.1.1.1.0.0
.1.1.0.1.0.0.1.1
.0.1.1.0.0.0.1.0
.0.1.0.0.0.1.1.0
.1.1.0.0.1.0.1.1
.0.0.1.1.1.1.0.0
.0.0.1.0.0.1.0.0
CROSSREFS
Sequence in context: A201599 A246636 A146794 * A130739 A147412 A273116
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved