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 A222562 #26 May 15 2024 08:34:15
%S A222562 1,2,4,8,20,24,32,48,56,68,72,80,84,96,104,116,128,132,144,152,168,
%T A222562 176,180,192,200,212,224,228,240,260,264,272,276,288,296,308,312,320,
%U A222562 324,336,344,356,360,368,372,384,392,404,408,416,452,456,464,468,480,488
%N A222562 Numbers that are highest in their respective Collatz (3x+1) trajectories only.
%C A222562 This is effectively the complement of A176869 in A033496, excluding numbers which are also highest in trajectories less than the number itself.
%H A222562 T. D. Noe, <a href="/A222562/b222562.txt">Table of n, a(n) for n = 1..1000</a>
%t A222562 Collatz[n_] := NestWhileList[If[EvenQ[#], #/2, 3 # + 1] &, n, # > 1 &]; oldMax = {}; t = {}; Do[c = Collatz[n]; If[! MemberQ[oldMax, n] && Max[c] == n, AppendTo[t, n]]; oldMax = Union[oldMax, {Max[c]}], {n, 416}]; t (* _T. D. Noe_, Feb 28 2013 *)
%Y A222562 Cf. A033496, A176869.
%K A222562 nonn
%O A222562 1,2
%A A222562 _Jayanta Basu_, Feb 27 2013