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%I A106830 #8 Feb 17 2018 13:45:16
%S A106830 0,1,5,5,31,31,247,247,247,247,2927,2927,40361,40361,40361,40361,
%T A106830 716167,716167,14117683,14117683,14117683,14117683,334406399,
%U A106830 334406399,334406399,334406399,334406399,334406399,9920878441,9920878441,314016924901,314016924901
%N A106830 Numerator of Sum_{ primes p <= n} 1/p.
%C A106830 Very similar to A024451, which see for further information.
%H A106830 Harvey P. Dale, <a href="/A106830/b106830.txt">Table of n, a(n) for n = 1..1000</a>
%e A106830 0, 1/2, 5/6, 5/6, 31/30, 31/30, 247/210, 247/210, 247/210, 247/210, 2927/2310, 2927/2310, 40361/30030, 40361/30030, 40361/30030, ...
%t A106830 Accumulate[Table[If[PrimeQ[n],1/n,0],{n,40}]]//Numerator (* _Harvey P. Dale_, Feb 17 2018 *)
%Y A106830 Denominators are in A034386.
%Y A106830 The following fractions are all related to each other: Sum 1/n: A001008/A002805, Sum 1/prime(n): A024451/A002110 and A106830/A034386, Sum 1/nonprime(n): A282511/A282512, Sum 1/composite(n): A250133/A296358.
%K A106830 nonn,frac
%O A106830 1,3
%A A106830 _N. J. A. Sloane_, May 22 2005

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