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 A170816 #2 Mar 30 2012 18:52:38 %S A170816 1,4,3,5,5,8,9,11,15,16,21,23,23,26,31,35,36,41,44,45,49,51,56,63,66, %T A170816 67,69,70,73,85,87,92,93,101,102,107,112,115,119,124,125,134,135,137, %U A170816 137,148,159,162,163,165,170,171,179,183,188,193,194,199,201,202,211,223 %N A170816 a(n)=A140475(n)-A141468(n). %e A170816 a(1)=1-0=1, a(2)=5-1=4, a(3)=7-4=3, a(4)=11-6=5, a(5)=13-8=5, a(6)=17-9=8. %Y A170816 Cf. A140475, A141468. %K A170816 nonn %O A170816 1,2 %A A170816 _Juri-Stepan Gerasimov_, Dec 07 2009