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 A274152 #12 Jul 04 2016 03:53:09
%S A274152 1,1,1,2,2,4,6,8,12,18,28,42,62,96,142,210,316,474,712,1070,1606,2410,
%T A274152 3608,5412,8124,12184,18268,27404,41114,61662,92484,138702,208020,
%U A274152 311988,467928,701866,1052812,1579204,2368764,3553048,5329306,7993478,11989564,17983626,26974744,40461664,60692460
%N A274152 Number of integers in n-th generation of tree T(3/2) defined in Comments.
%C A274152 Let T* be the infinite tree with root 0 generated by these rules: if p is in T*, then p+1 is in T* and x*p is in T*. Let g(n) be the set of nodes in the n-th generation, so that g(0) = {0}, g(1) = {1}, g(2) = {2,x}, g(3) = {3,2x,x+1,x^2}, etc. Let T(r) be the tree obtained by substituting r for x.
%C A274152 See A274142 for a guide to related sequences.
%H A274152 Kenny Lau, <a href="/A274152/b274152.txt">Table of n, a(n) for n = 0..73</a>
%e A274152 For r = 3/2, we have g(3) = {3,2r,r+1, r^2}, in which the number of integers is a(3) = 2.
%t A274152 z = 18; t = Join[{{0}}, Expand[NestList[DeleteDuplicates[Flatten[Map[{# + 1, x*#} &, #], 1]] &, {1}, z]]];
%t A274152 u = Table[t[[k]] /. x -> 3/2, {k, 1, z}];
%t A274152 Table[Count[Map[IntegerQ, u[[k]]], True], {k, 1, z}]
%Y A274152 Cf. A274142.
%K A274152 nonn,easy
%O A274152 0,4
%A A274152 _Clark Kimberling_, Jun 11 2016
%E A274152 More terms from _Kenny Lau_, Jul 02 2016