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A024530
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Numerator of -Sum_{k=1..n} (-1)^k / prime(k).
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11
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0, 1, 1, 11, 47, 727, 7141, 151427, 2366603, 64131559, 1636722341, 57208085801, 1916138684507, 85982424199597, 3392993977055461, 172553478253276697, 8530444564835173531, 535885387802465283059, 30766248305796169627529
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OFFSET
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0,4
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COMMENTS
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LINKS
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FORMULA
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a(n+1) = a(n)*prime(n+1) + (-1)^n*primorial(prime(n)) for n >= 2. - Alexandre Herrera, Sep 03 2023
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EXAMPLE
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0/1, 1/2, 1/6, 11/30, 47/210, 727/2310, 7141/30030, 151427/510510, ...
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MAPLE
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A024530 := n->numer(add((-1)^(k+1)/ithprime(k), k=1..n));
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MATHEMATICA
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a[n_] := Numerator[ -Total[(-1)^Range[n] / Prime[ Range[n]]]]; Table[a[n], {n, 0, 18}] (* Jean-François Alcover, Dec 12 2011 *)
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PROG
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(PARI)
a(n)=numerator(-sum(k=1, n, (-1)^k/prime(k)));
concat(0, vector(33, n, a(n))) /* show terms */
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CROSSREFS
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KEYWORD
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nonn,frac,easy,nice
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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