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 A151735 #2 Mar 30 2012 16:51:06 %S A151735 0,1,4,5,10,11,16,21,32,33,38,43,54,61,76,95,118,119,124,129,140,147, %T A151735 162,181,204,211,226,247,276,305,354,413,460,461,466,471,482,489,504, %U A151735 523,546,553,568,589,618,647,696,755,802,809,824,845,874,903,952,1013,1066,1095,1146 %N A151735 a(0)=0, a(1)=1; for n>21, a(n) = (A151725(n)+7)/4. %C A151735 The number of cells after n generations in one quadrant of the CA in A151725. %C A151735 The first differences (starting at a(2)) give A151737. %Y A151735 Cf. A151746. %K A151735 nonn %O A151735 0,3 %A A151735 _N. J. A. Sloane_, Jun 15 2009