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A209587
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Number of n X n 0..2 arrays with every element equal to a diagonal or antidiagonal reflection
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1
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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a(n) = 3 ^ (2*n-(n modulo 2)) * 15 ^ ((n*n-2*n+(n modulo 2))/4)
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EXAMPLE
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Some solutions for n=3
..1..1..1....2..0..1....0..1..1....2..0..2....2..0..0....0..2..1....0..2..0
..1..2..2....0..1..2....1..2..1....2..1..0....0..0..0....2..1..0....1..1..2
..0..2..0....1..2..0....0..1..2....1..2..0....0..0..1....1..0..2....0..1..2
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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