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A252522
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Number of (n+2)X(7+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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2176, 9069, 39689, 96659, 581529, 2662952, 6486931, 38674076, 177771524, 432970668, 2576695286, 11849993914, 28861601874, 171722924036, 789791249282, 1923610959226, 11444904413552, 52638098030182, 128205198751454
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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) = 86*a(n-3) -1415*a(n-6) +8680*a(n-9) -22666*a(n-12) +28036*a(n-15) -15888*a(n-18) +3168*a(n-21) for n>29
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EXAMPLE
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Some solutions for n=4
..3..2..0..3..2..0..3..2..0....1..2..2..1..2..2..1..2..2
..3..2..3..3..2..3..3..2..3....2..3..0..2..3..3..2..3..3
..2..1..2..2..1..2..2..1..2....2..3..3..2..3..3..2..0..3
..0..2..3..0..2..3..3..2..0....1..2..2..1..2..2..1..2..2
..3..2..3..3..2..0..3..2..3....2..3..3..2..3..3..2..3..3
..2..1..2..2..1..2..2..1..2....2..3..3..2..0..3..2..3..3
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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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