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A252012
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Number of (n+2)X(5+2) 0..3 arrays with every 3X3 subblock row and column sum 1 3 6 or 8 and every diagonal and antidiagonal sum not 1 3 6 or 8
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1
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1970, 3128, 4770, 8482, 23074, 58970, 104034, 288370, 744818, 1308322, 3648082, 9501482, 16654562, 46626322, 122075402, 213680482, 599752402, 1575429482, 2755215842, 7745663122, 20388177482, 35636762722, 100284675922, 264307061162
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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) = a(n-1) +21*a(n-3) -21*a(n-4) -104*a(n-6) +104*a(n-7) for n>16
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EXAMPLE
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Some solutions for n=4
..0..1..2..3..1..2..3....2..3..1..2..0..1..2....1..1..1..1..1..1..1
..2..1..3..2..1..0..2....1..1..1..1..1..1..1....2..0..1..2..3..1..2
..1..1..1..1..1..1..1....0..2..1..3..2..1..3....3..2..1..0..2..1..0
..3..1..2..3..1..2..3....2..3..1..2..0..1..2....1..1..1..1..1..1..1
..2..1..3..2..1..0..2....1..1..1..1..1..1..1....2..3..1..2..3..1..2
..1..1..1..1..1..1..1....3..2..1..0..2..1..3....3..2..1..0..2..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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