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A252533
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Number of (1+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 3 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 3 6 or 7
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1
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750, 730, 621, 719, 778, 932, 1200, 1498, 1968, 2708, 3473, 4698, 6444, 8494, 11435, 15560, 20630, 27462, 36761, 48910, 64407, 85224, 113390, 148048, 193940, 258080, 334681, 435134, 578923, 746716, 964795, 1283490, 1648229, 2118894, 2818420
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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) = 4*a(n-3) -3*a(n-6) -4*a(n-9) +4*a(n-12) for n>39
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EXAMPLE
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Some solutions for n=4
..2..2..2..3..1..3....3..1..3..3..1..3....3..3..0..0..0..3....1..1..0..1..1..0
..2..1..0..1..1..0....2..2..3..2..2..3....3..2..2..3..1..3....3..0..0..3..0..3
..1..2..3..1..3..2....3..2..2..3..1..2....2..3..2..1..3..2....1..0..1..1..0..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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