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 A248870 #11 Oct 13 2017 21:38:16
%S A248870 0,1,1,3,8,23,62,181,513,1513,4476,13483,40933,125845,389769,1217590,
%T A248870 3828775,12115966,38546124,123238296,395725493,1275733730,4127339091,
%U A248870 13396443708,43610621823,142354979662,465838195260,1527905193504,5022061115901,16539625666670,54571760414658
%N A248870 Satisfies Sum_{n>=0} a(n)*x^n = x / Product_{n>=0} (1 - x^n/(1 - x^n))^a(n).
%C A248870 Which kind of trees is counted by this sequence (compare to A000081, A004111, A073075, A248869 and A115593)?
%Y A248870 Cf. A248869.
%K A248870 nonn
%O A248870 0,4
%A A248870 _Joerg Arndt_, Mar 04 2015