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A252520
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Number of (n+2)X(5+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 2 4 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 2 4 6 or 7
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1
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1093, 2492, 8354, 17804, 74181, 268555, 581529, 2449868, 9015835, 19533141, 82653526, 306473786, 663815208, 2816595425, 10483644117, 22703178745, 96473171480, 359788629017, 779072416553, 3313087720630, 12368384154874
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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) = 64*a(n-3) -1282*a(n-6) +10153*a(n-9) -38844*a(n-12) +79176*a(n-15) -91088*a(n-18) +63696*a(n-21) -29380*a(n-24) +8949*a(n-27) -1580*a(n-30) +142*a(n-33) -5*a(n-36) for n>39
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EXAMPLE
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Some solutions for n=4
..0..3..2..3..3..2..0....0..3..2..0..3..2..3....2..2..1..2..2..1..2
..3..3..2..0..3..2..3....2..2..1..2..2..1..2....3..3..2..0..3..2..3
..2..2..1..2..2..1..2....3..3..2..3..3..2..3....3..0..2..3..3..2..0
..3..3..2..3..3..2..3....3..3..2..3..3..2..3....2..2..1..2..2..1..2
..3..3..2..0..3..2..0....2..2..1..2..2..1..2....0..3..2..3..3..2..3
..2..2..1..2..2..1..2....0..3..2..3..3..2..3....3..3..2..3..3..2..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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