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A183647
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Number of (n+1) X 5 0..4 arrays with every 2 X 2 subblock summing to 8.
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1
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5725, 12785, 33325, 97145, 307525, 1037585, 3684925, 13653545, 52436725, 207712385, 845452525, 3525617945, 15026853925, 65331315185, 289222676125, 1301655470345, 5946166679125, 27529329445985, 128980999355725
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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) = 15*a(n-1) - 85*a(n-2) + 225*a(n-3) - 274*a(n-4) + 120*a(n-5).
Empirical g.f.: 5*x*(1145 - 14618*x + 65635*x^2 - 120826*x^3 + 75000*x^4) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)*(1 - 5*x)). - Colin Barker, Apr 01 2018
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EXAMPLE
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Some solutions for 3 X 5:
3 3 3 3 3 1 2 1 4 2 0 4 0 3 0 1 4 0 3 3
0 2 0 2 0 1 4 1 2 0 3 1 3 2 3 2 1 3 2 0
2 4 2 4 2 2 1 2 3 3 1 3 1 2 1 2 3 1 2 4
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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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