

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
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OFFSET

0,1


COMMENTS

Semiprime analog of A136271. The absolute value of the first derivative of the semiprime zeta function at 2.


LINKS

Table of n, a(n) for n=0..58.
R. J. Mathar, Series of reciprocal powers of kalmost 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: A173823 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



