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 A092293 #4 Feb 22 2013 14:39:01 %S A092293 2,3,7,9,13,17,19,23,24,27,31,35,37,41,42,47,48,52,55,59,60,65,66,70, %T A092293 72,76,80,81,85,89,91,95,96,101,102,106,109,113,114,119,120,124,126, %U A092293 130,134,137,138,142,144,148,152 %N A092293 a(n) = 3*n + A090239(n). %C A092293 This sequence has asymptotic density 1/3. %K A092293 easy,nonn %O A092293 0,1 %A A092293 _Philippe Deléham_, Feb 05 2004