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 A115854 #5 Oct 19 2017 03:15:01 %S A115854 0,0,0,19,214,2154,19974,179590,1610937,14515403,131560754,1199914216, %T A115854 11009605949,101581094033,942018562525 %N A115854 Difference between number of semiprimes <= 10^n and the asymptotic approximation round(10^n*loglog(10^n)/log(10^n)). %e A115854 a(5) = A036352(5) - round(...10^5...) = 23378 - 21224 = 2154. %Y A115854 Cf. A001358, A036352, A066265, A072000. %K A115854 nonn %O A115854 0,4 %A A115854 _Jonathan Vos Post_, Mar 14 2006 %E A115854 Edited by _Don Reble_, Mar 29 2006