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A252381
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Number of (n+2) X (5+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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3020, 1067, 963, 1091, 1305, 1667, 2031, 2598, 3526, 4492, 5983, 8393, 10935, 14845, 21135, 27803, 38046, 54494, 71964, 98787, 141829, 187579, 257809, 370475, 490263, 674134, 969078, 1282700, 1764087, 2536241, 3357327, 4617621, 6639127, 8788771
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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*(3020 + 1067*x + 963*x^2 - 10989*x^3 - 2963*x^4 - 2185*x^5 + 9747*x^6 + 1646*x^7 + 710*x^8 - 2288*x^9 - 256*x^10 - 6*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:
..1..0..2..1..3..2..1....2..3..0..2..1..0..2....0..2..3..0..0..3..0
..0..0..0..3..0..0..3....0..1..2..0..1..2..3....2..1..3..2..1..3..2
..0..1..2..0..1..2..0....0..0..0..0..0..0..3....0..1..2..0..1..2..0
..1..3..2..1..3..2..1....2..1..0..2..1..0..2....0..0..3..0..0..3..0
..3..0..0..3..0..0..3....0..1..2..0..1..2..3....2..1..3..2..1..3..1
..0..1..2..0..1..2..0....0..0..0..0..0..0..3....0..1..2..0..1..2..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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