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A144971
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Integers of the form sum_{i=2521..j} i/(i-2520) for any upper limit j.
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0
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OFFSET
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1,1
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LINKS
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EXAMPLE
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The sum of the fractions i/(i-2520) over 2521<=i<=j is integer for upper limits j=2521 up to j=2530, which define the first 10 values of the sequence, for example a(3) = 2521/(2521-2520) +2522/(2522-2520) +2523/(2523-2520) = 4623.
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MATHEMATICA
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lst={}; q=2520; s=0; Do[s+=n/(n-q); If[s==IntegerPart[s], AppendTo[lst, s]], {n, q+1, q+4!}]; lst
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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Rephrased definition. Changed offset to 1. Added example. - R. J. Mathar, Oct 01 2008
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STATUS
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approved
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