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 A067305 #3 Mar 31 2012 13:20:07 %S A067305 1,5,36,328,3440,39408,478912,6068480,79315200,1061628160,14480086016, %T A067305 200540018688,2812618092544,39867889037312,570237130752000, %U A067305 8219880968028160,119293333282291712,1741605394647416832 %N A067305 Second column of triangle A067304. %F A067305 a(n)= A067304(n+1, 1) = A067297(n+1) - A064340(n+1), n>=0. %F A067305 G.f.: 4*(3+c(4*x))*(c(4*x)^3)/(1+c(4*x))^4 with c(x) g.f. of A000108 (Catalan). %K A067305 nonn,easy %O A067305 0,2 %A A067305 _Wolfdieter Lang_, Feb 05 2002