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A252382
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Number of (n+2) X (6+2) 0..3 arrays with every 3 X 3 subblock row and diagonal sum equal to 0 3 5 6 or 7 and every 3 X 3 column and antidiagonal sum not equal to 0 3 5 6 or 7.
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1
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4682, 1496, 1341, 1475, 1894, 2356, 2778, 3836, 5035, 6189, 8920, 12049, 15119, 22230, 30412, 38498, 57076, 78487, 99705, 148304, 204349, 259947, 387142, 533860, 679466, 1012428, 1396531, 1777781, 2649448, 3655033, 4653207, 6935222, 9567868
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OFFSET
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1,1
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LINKS
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FORMULA
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Empirical: a(n) = 4*a(n-3) - 4*a(n-6) + a(n-9) for n>12.
Empirical g.f.: x*(4682 + 1496*x + 1341*x^2 - 17253*x^3 - 4090*x^4 - 3008*x^5 + 15606*x^6 + 2244*x^7 + 975*x^8 - 3705*x^9 - 344*x^10 - 8*x^11) / ((1 - x)*(1 + x + x^2)*(1 - 3*x^3 + x^6)). - Colin Barker, Dec 03 2018
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EXAMPLE
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Some solutions for n=4:
..3..1..2..0..1..2..3..1....2..3..0..2..1..3..2..1....0..1..2..0..1..2..0..1
..1..0..2..1..0..2..1..0....0..1..2..0..1..2..0..1....0..0..3..0..0..3..0..0
..0..0..0..0..3..0..0..0....0..0..0..0..0..3..0..0....2..1..3..2..1..3..2..1
..0..1..2..3..1..2..0..1....2..1..0..2..1..3..2..1....0..1..2..0..1..2..0..1
..1..0..2..1..0..2..1..0....0..1..2..0..1..2..0..1....0..0..3..0..0..3..0..0
..0..3..0..0..0..0..0..3....0..0..0..0..0..3..2..0....2..1..3..2..1..3..1..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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