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A255227
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Number of (n+2)X(7+2) 0..1 arrays with no 3x3 subblock diagonal sum 0 and no antidiagonal sum 0 and no row sum 2 and no column sum 2
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1
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127, 133, 142, 154, 172, 199, 238, 295, 379, 502, 682, 946, 1333, 1900, 2731, 3949, 5734, 8350, 12184, 17803, 26038, 38107, 55795, 81718, 119710, 175390, 256993, 376588, 551863, 808741, 1185214, 1736962, 2545588, 3730687, 5467534, 8013007
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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) = 2*a(n-1) -a(n-2) +a(n-3) -a(n-4)
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EXAMPLE
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Some solutions for n=4
..1..0..0..0..1..0..0..1..0....1..0..0..1..0..0..0..0..1
..1..0..0..0..1..0..0..1..0....1..0..0..1..0..0..0..0..1
..1..1..1..1..1..1..1..1..1....1..1..1..1..1..1..1..1..1
..1..0..0..0..1..0..0..1..0....1..0..0..1..0..0..0..0..1
..1..0..0..0..1..0..0..1..0....1..0..0..1..0..0..0..0..1
..1..1..1..1..1..1..1..1..1....1..1..1..1..1..1..1..1..1
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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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