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A252208
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Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 1 3 4 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 1 3 4 6 or 7
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1
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125554, 932474, 22430534, 84935426, 2778728210, 78534150994, 267361717782, 9906342079298, 303070072293522, 959873651074130, 38221223204833202, 1212189579390626626, 3685070395096108374, 152413070389286672834
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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) = 7180*a(n-3) -14766111*a(n-6) +8766317556*a(n-9) -103534211040*a(n-12) +266111582208*a(n-15) +103548977152*a(n-18) -274877906944*a(n-21) for n>24
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EXAMPLE
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Some solutions for n=1
..0..2..2..3..2..2..0..2....0..1..0..0..1..3..3..1....2..2..0..1..2..1..0..2
..3..0..0..1..3..3..1..2....1..2..1..1..2..1..1..1....1..0..3..0..1..0..3..0
..0..2..2..3..2..2..3..2....3..1..3..3..1..0..0..1....0..1..3..0..0..3..3..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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