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 A245142 #4 Jul 12 2014 17:46:10 %S A245142 1,0,1,1,3,3,8,9,21,28,56,81,159,237,444,701,1273,2060,3699,6099, %T A245142 10840,18180,32079,54417,95787,163868,287914,496171,871270,1509676, %U A245142 2652068,4615810,8114578,14176261,24947471,43718822,77031659,135350915,238791685,420544851 %N A245142 Number of n-node unlabeled rooted trees with thickening limbs and root outdegree (branching factor) 2. %H A245142 Alois P. Heinz, <a href="/A245142/b245142.txt">Table of n, a(n) for n = 3..150</a> %Y A245142 Column k=2 of A245151. %K A245142 nonn %O A245142 3,5 %A A245142 _Alois P. Heinz_, Jul 12 2014