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 A213330 #15 Oct 13 2022 22:31:41
%S A213330 0,1,1,2,1,1,1,4,1,2,1,2,3,1,1,8,1,1,1,4,5,2,3,8,1,6,4,2,3,5,4,16,1,6,
%T A213330 5,2,3,2,1,20,1,10,3,4,5,6,1,24,3,2,1,12,13,1,2,4,1,6,1,7,8,1,2,32,9,
%U A213330 8,9,16,17,10,1,20,2,18,10,12,11,2,3,40,1,2
%N A213330 Minimum deviation from n in Collatz trajectory of n.
%C A213330 Assuming Collatz trajectory ends with 1 and also a(1)=0.
%H A213330 T. D. Noe, <a href="/A213330/b213330.txt">Table of n, a(n) for n = 1..10000</a>
%e A213330 a(4)=2 because the number closest to 4 in Collatz trajectory of 4 is 2.
%t A213330 Collatz[n_] := NestWhileList[If[EvenQ[#], #/2, 3 # + 1] &, n, # > 1 &]; Join[{0}, Table[Min[Rest[Abs[Collatz[n] - n]]], {n, 2, 100}]]
%Y A213330 Cf. A070165, A355239 (indices of 1's).
%K A213330 nonn
%O A213330 1,4
%A A213330 _Jayanta Basu_, Mar 03 2013