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A147025
Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 01000-11111-01000 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 1, 3, 15, 21, 45, 77, 273, 569, 2606, 6661, 31883, 89951, 535540, 1839325, 13532589, 55467031, 467306429, 2229430591, 22257836225
OFFSET
1,8
EXAMPLE
Maximal 8 X 8 example
.0.0.0.1.0.0.1.0
.1.1.1.1.1.0.1.0
.0.0.0.1.0.0.1.0
.0.1.0.0.0.1.1.1
.1.1.1.0.0.0.1.0
.0.1.0.0.1.0.0.0
.0.1.0.1.1.1.1.1
.0.1.0.0.1.0.0.0
CROSSREFS
Sequence in context: A110172 A261274 A014493 * A147017 A171570 A350987
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved