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A146270
Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 110-111-110 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 8, 19, 32, 51, 140, 477, 1662, 6189, 24619, 109450, 533450, 2859993, 16886952, 110380054, 797354362, 6460189913, 58366269898, 572562441744, 6143132227217, 72768344185209
OFFSET
1,7
EXAMPLE
Maximal 8 X 8 example
.0.0.0.0.1.1.0.0
.0.1.0.0.1.1.1.0
.1.1.1.0.1.1.0.0
.1.1.1.0.0.0.0.0
.0.0.0.0.0.1.1.1
.0.0.1.1.0.1.1.1
.0.1.1.1.0.0.1.0
.0.0.1.1.0.0.0.0
CROSSREFS
Sequence in context: A260004 A144171 A017485 * A146222 A140672 A230098
KEYWORD
nonn
AUTHOR
STATUS
approved