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A146133
Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 3X2 zee 1,1 1,2 1,3 2,3 2,4 in any orientation.
0
1, 1, 1, 1, 1, 3, 17, 33, 85, 255, 1137, 4265, 27311, 122911, 972783, 6003645, 62308027, 499428829, 6712583897, 70003989585, 1225387976695, 16725199996985
OFFSET
1,6
EXAMPLE
Maximal 8 X 8 example
.0.0.0.0.1.0.0.0
.0.0.0.0.1.1.0.0
.0.1.1.1.0.1.0.0
.1.1.0.0.0.1.0.0
.0.0.1.0.0.0.1.1
.0.0.1.0.1.1.1.0
.0.0.1.1.0.0.0.0
.0.0.0.1.0.0.0.0
CROSSREFS
Sequence in context: A309744 A115355 A146021 * A297735 A266062 A031290
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 27 2008
STATUS
approved