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A282512
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Denominator of the sum of the reciprocals of the first n nonprimes.
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9
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1, 4, 12, 24, 72, 360, 360, 2520, 504, 1008, 336, 1680, 1680, 18480, 18480, 92400, 1201200, 10810800, 10810800, 10810800, 21621600, 21621600, 367567200, 52509600, 52509600, 997682400, 997682400, 997682400, 6983776800, 6983776800, 6983776800, 160626866400, 160626866400, 1124388064800, 1124388064800
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OFFSET
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1,2
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LINKS
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EXAMPLE
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The first few fractions are 1, 5/4, 17/12, 37/24, 119/72, 631/360, 661/360, 4807/2520, 995/504, 2053/1008, 703/336, 3599/1680, ... - N. J. A. Sloane, Dec 15 2017
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MAPLE
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NP:= remove(isprime, [$1..100]):
S:= ListTools:-PartialSums(map(t -> 1/t, NP)):
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MATHEMATICA
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With[{nn=50}, Denominator@Accumulate[1/Complement[Range@nn, Prime@Range@PrimePi@nn]]] (* Vincenzo Librandi, May 02 2017 *)
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CROSSREFS
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KEYWORD
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nonn,frac
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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