This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A154928 #13 Jul 29 2025 12:02:03
%S A154928 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,
%T A154928 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
%N A154928 Decimal expansion of Sum_{q in A001358} log(q)/q^2 over the semiprimes q = 4,6,9,...
%C A154928 Semiprime analog of A136271. The absolute value of the first derivative of the semiprime zeta function at 2.
%H A154928 R. J. Mathar, <a href="http://arxiv.org/abs/0803.0900">Series of reciprocal powers of k-almost primes</a>, arXiv:0803.0900 [math.NT], 2008-2009; see Table 4 in version 3.
%F A154928 Equals Sum_{j>=1} log(A001358(j))/A074985(j).
%e A154928 Equals 0.0283606815... = log(4)/16 + log(6)/36 + log(9)/81 + ....
%K A154928 cons,nonn,more
%O A154928 0,2
%A A154928 _R. J. Mathar_, Jan 17 2009
%E A154928 Missing zero inserted. _Artur Jasinski_, Jul 29 2025