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A216059 Smallest number not in Collatz trajectory starting at n.

%I A216059 #14 Feb 16 2025 08:33:18
%S A216059 2,3,6,3,3,7,3,3,3,3,3,7,3,3,3,3,3,3,3,3,3,3,3,7,3,3,3,3,3,3,3,3,3,3,
%T A216059 3,3,3,3,3,3,3,3,3,3,3,3,3,7,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,
%U A216059 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3
%N A216059 Smallest number not in Collatz trajectory starting at n.
%C A216059 a(n) <= 7; a(A007283(n)) = 7;
%C A216059 a(n) <> 4; a(n) <> 4; a(n) <> 6 for n > 3;
%C A216059 a(n) = A216022(n) + 1.
%H A216059 Reinhard Zumkeller, <a href="/A216059/b216059.txt">Table of n, a(n) for n = 1..1000</a>
%H A216059 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/CollatzProblem.html">Collatz Problem</a>
%H A216059 Wikipedia, <a href="http://en.wikipedia.org/wiki/Collatz_conjecture">Collatz conjecture</a>
%H A216059 <a href="/index/3#3x1">Index entries for sequences related to 3x+1 (or Collatz) problem</a>
%t A216059 scoll[n_]:=Sort[NestWhileList[If[EvenQ[#],#/2,3#+1] &,n,#>1 &]]; Join[{2,3},Table[i=1; While[scoll[n][[i]]==i,i++]; i,{n,3,86}]] (* _Jayanta Basu_, May 27 2013 *)
%o A216059 (Haskell)
%o A216059 import Data.List ((\\))
%o A216059 a216059  n = head $ enumFromTo 1 (maximum ts + 1) \\ ts
%o A216059    where ts = a070165_row n
%Y A216059 Cf. A006370, A070165.
%K A216059 nonn
%O A216059 1,1
%A A216059 _Reinhard Zumkeller_, Sep 01 2012