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 A175961 #4 Mar 30 2012 18:52:40 %S A175961 1,4,4,4,4,6,6,6,6,6,6,8,8,8,8,8,8,8,8,9,9,9,9,9,9,9,9,9,10,10,10,10, %T A175961 10,10,10,10,10,10,12,12,12,12,12,12,12,12,12,12,12,12,14,14,14,14,14, %U A175961 14,14,14,14,14,14,14,14,14,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15 %N A175961 n-th nonprime number appears n-th nonprime numbers times. %C A175961 A018252(n) appears A018252(n) times; 1 appears once, n-th composite number appears n-th composite number times; 1 together with A111655. %F A175961 a(1)=1, a(n+1)=A111655(n). %Y A175961 Cf. A063905, A141468, A175944. %K A175961 nonn,easy,less %O A175961 1,2 %A A175961 _Juri-Stepan Gerasimov_, Oct 31 2010