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 A134421 #3 Mar 30 2012 18:50:59 %S A134421 1,2,4,6,8,11,14,17,20,23,26,29,32,35,39,43,47,51,55,59,63,67,71,75, %T A134421 79,83,87,91,95,99,103,107,111,115,119,123,127,131,135,139,143,148, %U A134421 153,158,163,168,173,178,183,188,193,198,203,208,213,218,223,228,233,238,243 %N A134421 Partial sums of A134021. %C A134421 a(n) = if n=0 then A134021(0) else a(n-1)+A134021(n); %C A134421 n = Sum(A059095(a(n)-2-k)*3^k: 0<=k < A134021(n)), for n>0. %K A134421 nonn %O A134421 0,2 %A A134421 _Reinhard Zumkeller_, Oct 25 2007