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A251813
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Number of (n+2)X(2+2) 0..2 arrays with every row, column, diagonal or antidiagonal in each 3X3 subblock summing to a prime
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1
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500, 538, 771, 1511, 3501, 9040, 24411, 66516, 182350, 501847, 1381865, 3805521, 10483208, 28880671, 79563282, 219191950, 603867313, 1663633281, 4583249193, 12626700608, 34786146677, 95834675528, 264021359180, 727370137909
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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) +2*a(n-2) +9*a(n-3) +2*a(n-4) -5*a(n-5) -23*a(n-6) -14*a(n-7) +2*a(n-8) +25*a(n-9) +20*a(n-10) +4*a(n-11) -12*a(n-12) -11*a(n-13) -4*a(n-14) +2*a(n-15) +2*a(n-16) +a(n-17) for n>25
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EXAMPLE
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Some solutions for n=4
..0..1..2..0....0..2..0..0....2..1..2..2....1..1..0..1....0..1..1..1
..2..0..1..2....1..0..1..1....1..1..1..0....0..1..1..1....1..1..1..1
..0..1..2..0....2..1..2..2....0..0..2..0....1..1..1..1....1..1..1..1
..0..1..2..0....0..2..0..0....2..1..2..2....1..0..1..1....1..1..1..0
..2..0..1..2....1..0..1..1....0..1..1..0....1..1..1..0....1..1..1..1
..0..1..2..0....2..1..2..2....0..0..2..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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