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 A067300 #3 Mar 31 2012 13:20:07 %S A067300 3,12,100,1024,11632,140864,1782080,23273984,311407360,4246776832, %T A067300 58812433408,824868814848,11692779565056,167254617440256, %U A067300 2411126992093184,34994856661483520,510941885186637824 %N A067300 One third of third column of triangle A067298. %F A067300 a(n)=A067298(n+2, 2)/3. %F A067300 G.f.: ((1-4*x)*c(4*x)+2)/(1-2*x*c(4*x))^2, with c(x) is g.f. for A000108 (Catalan). %Y A067300 Cf. A067299 (second column), 8*A067301 (fourth column). %K A067300 nonn,easy %O A067300 0,1 %A A067300 _Wolfdieter Lang_, Feb 05 2002