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 A154937 #7 Oct 05 2024 14:48:11
%S A154937 2,0,9,7,8,8,3,2,3,9,4,0,0,1,9,4,9,2,7,5,5,3,6,8,6,0,2,4,6,9,1,8,9,2,
%T A154937 3,6,2,6,8,6,1,3,9,3,2,9,2,1,8,5,1,3,4,3,7,5,2,8,1,7
%N A154937 Decimal expansion of sum_q 1/(q-1)^2 over the semiprimes q = 4,6,9,10,...
%C A154937 Semiprime analog of A086242.
%H A154937 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], Table 11.
%F A154937 Equals Sum_{i>=1} 1/(A001358(i)-1)^2.
%e A154937 Equals 0.2097883239400194927... = 1/3^2+1/5^2+1/8^2+1/9^2+1/13^2+...
%K A154937 cons,nonn
%O A154937 0,1
%A A154937 _R. J. Mathar_, Jan 17 2009