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 A210509 #20 Jan 28 2013 19:19:32
%S A210509 3,3,3,3,3,3,4,4,4,4,4,5,5,5,5,6,6,6,7,7,7,8,8,9,9,9,10,10,11,11,12,
%T A210509 13,13,14,15,15,16,17,18,18,19,20,21,22,23,25,26,27,28,30,31,33,34,36,
%U A210509 37,39,41,43,45,47,49,52,54,57,60,62,65,69,72,75,79,83,86
%N A210509 x(n+1) = x(n)*Pi/3 with x(0) = Pi, and a(n) = floor(x(n)).
%C A210509 24 is the first number greater than 3 not in the sequence.
%C A210509 Later output is more separated, for example: 40888572599, 42818413097, 44839337342, 46955644261.
%F A210509 x(n+1) = x(n)*Pi/3 with x(0) = Pi, and a(n) = floor(x(n)).
%o A210509 (JavaScript)
%o A210509 pi=Math.PI;
%o A210509 x=pi;
%o A210509 for (i=0;i<600;i++) {x*=pi;x/=3;document.write(Math.floor(x)+", ");}
%Y A210509 Cf. A000796 (Pi), A019670 (Pi/3).
%K A210509 nonn
%O A210509 0,1
%A A210509 _Jon Perry_, Jan 25 2013