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A252205
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Number of (n+2)X(3+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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9312, 17276, 110128, 332462, 2908856, 22430534, 65275092, 634915114, 5227154036, 14646511730, 151229828648, 1283725464674, 3514356997020, 37441377416842, 322401720094316, 871431684514562, 9433122571600616, 81784148775215954
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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) = 454*a(n-3) -60039*a(n-6) +2444346*a(n-9) -12981624*a(n-12) +14332416*a(n-15) +13041664*a(n-18) -16777216*a(n-21) for n>24
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EXAMPLE
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Some solutions for n=3
..0..0..1..0..0....3..3..1..3..0....1..3..0..1..0....3..3..1..0..3
..3..0..1..3..3....0..0..1..0..0....0..2..2..3..2....0..0..1..3..0
..1..1..2..1..1....1..1..2..1..1....3..2..2..3..2....1..1..2..1..1
..0..0..1..0..0....0..0..1..0..0....1..3..0..1..3....0..0..1..0..0
..0..3..1..0..3....3..0..1..3..3....3..2..2..3..2....0..3..1..0..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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