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A183997
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Number of (n+1) X 4 0..2 arrays with all 2 X 2 subblock sums the same.
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1
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361, 579, 977, 1887, 3793, 8415, 19217, 47031, 117601, 308799, 822977, 2268807, 6311953, 17963055, 51378737, 149156151, 434130241, 1275821919, 3754108577, 11115905127, 32933734513, 97974065295, 291541674257, 869866334871
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OFFSET
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1,1
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COMMENTS
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Column 3 of A184003.
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LINKS
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R. H. Hardin, Table of n, a(n) for n = 1..200
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FORMULA
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Empirical: a(n) = 6*a(n-1) - 60*a(n-3) + 85*a(n-4) + 150*a(n-5) - 360*a(n-6) + 396*a(n-8) - 216*a(n-9).
Empirical g.f.: x*(361 - 1587*x - 2497*x^2 + 17685*x^3 - 3474*x^4 - 59088*x^5 + 42012*x^6 + 60804*x^7 - 56376*x^8) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 2*x^2)*(1 - 3*x^2)*(1 - 6*x^2)). - Colin Barker, Apr 09 2018
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EXAMPLE
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Some solutions for 3 X 4:
..2..0..2..0....0..2..2..2....0..1..1..2....1..1..2..0....2..1..2..1
..2..2..2..2....2..1..0..1....1..2..0..1....2..0..1..1....1..2..1..2
..0..2..0..2....0..2..2..2....0..1..1..2....0..2..1..1....2..1..2..1
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CROSSREFS
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Cf. A184003.
Sequence in context: A325882 A255787 A219340 * A211822 A233552 A176899
Adjacent sequences: A183994 A183995 A183996 * A183998 A183999 A184000
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin, Jan 08 2011
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STATUS
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approved
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