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A145943
Number of n X n binary arrays with all ones connected in a 3X2 elbow 1,1 1,2 1,3 2,3 in any orientation.
0
1, 1, 17, 101, 1439, 45325, 2541179, 249765423, 48546882545, 17503645590565, 11722960747922791
OFFSET
1,3
EXAMPLE
Maximal 8 X 8 example
.1.1.1.0.1.1.1.0
.0.0.1.0.1.0.0.1
.1.1.0.0.0.1.1.1
.1.0.1.1.1.0.0.0
.1.0.0.0.1.0.1.1
.0.1.1.1.0.1.0.1
.1.0.0.1.0.1.0.1
.1.1.1.0.0.1.1.0
CROSSREFS
Sequence in context: A186258 A175518 A215234 * A331950 A234693 A022677
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 25 2008
STATUS
approved