A068589 revision #13
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A068589
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Denominator(Sum_{i=1..n} 1/i^3)/denominator(Sum_{i=1..n} 1/i).
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2
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1, 4, 36, 144, 3600, 1200, 58800, 235200, 6350400, 6350400, 768398400, 768398400, 129859329600, 129859329600, 129859329600, 519437318400, 150117385017600, 50039128339200, 18064125330451200, 18064125330451200, 54192375991353600
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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MAPLE
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a := proc(n) local i: denom(add(1/i^3, i = 1 .. n))/denom(add(1/i, i = 1 .. n)): end proc:
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PROG
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(PARI) a(n) = denominator(sum(k=1, n, 1/k^3)/sum(k=1, n, 1/k)); \\ Michel Marcus, May 07 2020
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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proposed
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