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A228733
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Number of arrays of the median of three adjacent elements of some length n+2 0..1 array.
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1
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2, 4, 8, 16, 28, 50, 88, 156, 278, 496, 886, 1582, 2824, 5040, 8994, 16050, 28642, 51114, 91218, 162788, 290512, 518448, 925222, 1651150, 2946640, 5258570, 9384438, 16747458, 29887496, 53337194, 95185500, 169867942, 303146148, 540994292
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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) = 2*a(n-1) -a(n-3) +a(n-5).
Empirical: G.f. -2*x*(1+x)*(x^2-x+1) / ( -1+2*x-x^3+x^5 ). - R. J. Mathar, Sep 02 2013
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EXAMPLE
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All solutions for n=4
..1..1..0..0..1..1..1..0..0..1..0..0..1..1..0..0
..0..1..0..0..0..1..0..1..1..1..0..1..1..0..1..0
..1..1..1..1..0..1..0..1..0..0..0..0..0..1..1..0
..1..1..1..0..1..0..0..0..0..0..1..1..1..0..1..0
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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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