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A146054
Number of n X n binary arrays with all ones connected only in a 2X3 U in any orientation.
0
1, 1, 9, 29, 153, 2069, 42313, 973281, 38746505, 2736250609, 283141781389, 43072398238613, 10634195356126331, 4171127160636409481, 2497710164925793120737
OFFSET
1,3
EXAMPLE
Maximal 8 X 8 example
.1.1.1.0.1.1.0.0
.1.0.1.0.1.0.1.1
.0.0.0.0.1.1.0.1
.1.0.1.0.0.0.1.1
.1.1.1.0.1.1.0.0
.0.0.0.0.1.0.1.1
.1.0.1.0.1.1.0.1
.1.1.1.0.0.0.1.1
CROSSREFS
Sequence in context: A147282 A146602 A146413 * A321588 A173262 A337445
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 26 2008
STATUS
approved