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A154943 Decimal expansion of the negated value of the sum_q [log(1-1/q)+1/q] over the semiprimes q. 0

%I #6 Jul 23 2013 15:15:51

%S 0,7,9,8,4,8,0,4,0,3,0,6,2,3,2,6,9,1,8,9,7,4,0,2,2,5,4,7,0,5,1,3,6,6,

%T 8,2,2,7,2,3,1,1,9,0,2,0,8,4,9,0,8,6,0,3

%N Decimal expansion of the negated value of the sum_q [log(1-1/q)+1/q] over the semiprimes q.

%C The semiprime analog of A143524. Taylor expansion of the logarithm shows that the value is sum_{s=2,3,..,infinity} P_2(s)/s, where P_2(s) are the semiprime zeta functions in Table 3 of the preprint arXiv:0803.0900. P_2(2)=A117543 and P_2(3)=0.023806..., P_2(4)=0.004994... etc.

%F Equals the negative of Sum_{i>=1} ( log(1-1/A001358(i)) +1/A001358(i)).

%e Equals 0.079848040306232691897402254...

%K cons,nonn

%O 0,2

%A _R. J. Mathar_, Jan 17 2009

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Last modified April 25 06:49 EDT 2024. Contains 371964 sequences. (Running on oeis4.)