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 A130050 #2 Mar 30 2012 18:57:10 %S A130050 3,7,12,20,29,39,50,63,77,92,108,126,145,166,188,211,235,260,286,313, %T A130050 341,371,402,435,469,504,540,577,615,655,696,738,781,825,870,916,963, %U A130050 1011,1060,1112,1165,1219,1274,1330,1387,1445,1504,1564,1625,1687,1751 %N A130050 A bisection of A120049. %C A130050 The other bisection is A130051; both bisections are strictly increasing. %F A130050 a(n)=b(2n), for n>=1, where b=A130049. %Y A130050 Cf. A130048, A130049, A130051. %K A130050 nonn %O A130050 1,1 %A A130050 _Clark Kimberling_, May 03 2007