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A209592
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Number of n X n 0..7 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) = 8 ^ (2*n-(n modulo 2)) * 120 ^ ((n*n-2*n+(n modulo 2))/4)
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EXAMPLE
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Some solutions for n=3
..0..3..3....0..2..7....0..3..7....0..4..0....0..7..7....0..7..5....0..4..0
..3..2..7....2..5..5....3..5..3....6..7..4....7..1..2....4..6..7....1..0..4
..4..7..0....7..5..0....3..3..0....6..6..0....7..2..0....5..4..0....1..1..0
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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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