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A154928 Decimal expansion of sum_{q in A001358} log(q)/q^2 over the semiprimes q = 4,6,9,... 0
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; 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: A201748 A011431 A173823 * A201394 A169844 A076123

Adjacent sequences:  A154925 A154926 A154927 * A154929 A154930 A154931

KEYWORD

cons,nonn

AUTHOR

R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 17 2009

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Last modified February 23 05:10 EST 2012. Contains 206606 sequences.