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A251875
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Number of (n+2)X(7+2) 0..3 arrays with every 3X3 subblock row and column sum not 2 4 5 or 7 and every diagonal and antidiagonal sum 2 4 5 or 7
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1
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32372, 99808, 40816, 62720, 267872, 506656, 893120, 3499888, 8000000, 15317248, 56450688, 146923792, 294439232, 1049159568, 2916709968, 5965120064, 20941831888, 59901392016, 123522690880, 431054317328, 1247133093840
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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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Empirical: a(n) = 29*a(n-3) -168*a(n-6) for n>17
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EXAMPLE
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Some solutions for n=4
..1..2..0..1..2..3..1..2..0....2..2..2..2..2..2..2..2..2
..0..3..3..3..0..3..0..3..0....1..0..2..1..0..2..1..3..2
..2..1..0..2..1..3..2..1..0....3..1..2..0..1..2..0..1..2
..1..2..3..1..2..0..1..2..3....2..2..2..2..2..2..2..2..2
..3..0..3..0..3..0..3..0..3....1..3..2..1..0..2..1..3..2
..2..1..3..2..1..0..2..1..3....0..1..2..3..1..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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