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 A026188 #4 Mar 30 2012 18:56:05 %S A026188 1,3,5,2,9,11,4,15,6,7,21,23,8,27,10,33,12,13,39,41,14,45,47,16,17,51, %T A026188 18,19,57,59,20,63,22,69,24,25,75,77,26,81,28,29,87,30,31,93,95,32,99, %U A026188 101,34,35,105,36,37,111,113,38,117,40,123 %N A026188 a(n) = (1/5)*s(n), where s(n) is the n-th multiple of 5 in A026136. %K A026188 nonn %O A026188 1,2 %A A026188 _Clark Kimberling_