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 A274146 #20 Jul 04 2016 03:53:34
%S A274146 1,1,1,1,1,2,2,3,3,5,5,7,8,11,12,16,18,24,28,35,41,53,63,79,95,119,
%T A274146 145,181,221,275,339,421,519,645,798,991,1228,1525,1890,2350,2915,
%U A274146 3622,4495,5588,6939,8626,10712,13315,16545,20567,25556,31766,39483,49081,61007,75836,94270,117194,145688
%N A274146 Number of integers in n-th generation of tree T(3/4) defined in Comments.
%C A274146 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 A274146 See A274142 for a guide to related sequences.
%H A274146 Kenny Lau, <a href="/A274146/b274146.txt">Table of n, a(n) for n = 0..10561</a>
%e A274146 For r = 3/4, we have g(3) = {3,2r,r+1, r^2}, in which only 3 is an integer, so that a(3) = 1.
%t A274146 z = 18; t = Join[{{0}}, Expand[NestList[DeleteDuplicates[Flatten[Map[{# + 1, x*#} &, #], 1]] &, {1}, z]]];
%t A274146 u = Table[t[[k]] /. x -> 3/4, {k, 1, z}];
%t A274146 Table[Count[Map[IntegerQ, u[[k]]], True], {k, 1, z}]
%Y A274146 Cf. A274142.
%K A274146 nonn,easy
%O A274146 0,6
%A A274146 _Clark Kimberling_, Jun 11 2016
%E A274146 More terms from _Kenny Lau_, Jul 01 2016