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 A154928 Decimal expansion of sum_{q in A001358} log(q)/q^2 over the semiprimes q = 4,6,9,... 1
 2, 8, 3, 6, 0, 6, 8, 1, 5, 4, 0, 7, 9, 8, 0, 6, 5, 2, 2, 2, 4, 2, 5, 8, 2, 2, 2, 5, 4, 8, 2, 7, 8, 3, 3, 6, 0, 7, 9, 3, 5, 0, 5, 7, 8, 2, 3, 7, 8, 1, 4, 0, 1, 3, 4, 1, 1, 1, 1 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS Semiprime analog of A136271. The absolute value of the first derivative of the semiprime zeta function at 2. LINKS R. J. Mathar, Series of reciprocal powers of k-almost primes, arXiv:0803.0900 [math.NT], Table 4. FORMULA Equals sum_{i=1,2,..,infinity} log(A001358(i))/A074985(i) . EXAMPLE Equals 0.283606815... = log(4)/16+log(6)/36+log(9)/81+.... CROSSREFS Sequence in context: A278115 A222296 A258223 * A201394 A169844 A076123 Adjacent sequences:  A154925 A154926 A154927 * A154929 A154930 A154931 KEYWORD cons,nonn AUTHOR R. J. Mathar, Jan 17 2009 STATUS approved

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Last modified December 10 05:49 EST 2018. Contains 318044 sequences. (Running on oeis4.)