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 A024968 #5 Oct 19 2017 03:13:45 %S A024968 2,4,6,9,10,12,14,16,19,20,24,26,27,29,30,32,33,36,37,40,42,43,44,47, %T A024968 49,52,55,58,59,61,64,66,67,69,70,71,74,75,78,79,83,84,86,87,88,90,95, %U A024968 96,98,101,102,105,106,109,112,114,117,118,119,121,122,124,126,127,129,131 %N A024968 Positions of even numbers in A003072. %K A024968 nonn %O A024968 1,1 %A A024968 _Clark Kimberling_ %E A024968 Corrected by _Don Reble_, Nov 19 2006