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 A167885 #5 Jul 12 2012 00:39:51 %S A167885 0,4,18,60,126,184,270,370,462,611,742,900,1072,1224,1501,1660,1869, %T A167885 2134,2448,2700,2938,3429,3668,4002,4650,5024,5379,5678,6055,6480, %U A167885 7296,7722,8440,9143,9804,10252,10800,11546,12336,12887,13500,14127,14664 %N A167885 n-th single or isolated number*n-th non-single or nonisolated number. %F A167885 a(n)=A167706(n)*A167707(n). %e A167885 a(1)=2*0=0, a(2)=4*1=4, a(3)=6*3=18, a(4)=12*5=60. %Y A167885 Cf. A167706, A167707. %K A167885 nonn %O A167885 1,2 %A A167885 _Juri-Stepan Gerasimov_, Nov 14 2009, Nov 15 2009 %E A167885 All terms > 1900 corrected by _R. J. Mathar_, May 30 2010