%I #9 Mar 01 2013 15:07:02
%S 0,1,4,2,4,4,11,3,11,4,11,4,8,11,10,4,11,11,17,7,6,11,10,10,17,8,34,
%T 11,17,10,34,5,25,11,10,11,20,17,24,8,34,6,26,11,15,10,34,11,23,17,21,
%U 11,10,34,34,19,26,17,24,10,18,34,34,6,26,25,24,14,13,10
%N Number of iterations in Collatz (3x+1) trajectory of n to reach 1 from the highest term.
%H T. D. Noe, <a href="/A222641/b222641.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A006577(n) - A220421(n);
%e Collatz trajectory of 5 is 5, 16, 8, 4, 2, 1. Hence, a(5) = 4.
%t Collatz[n_] := NestWhileList[If[EvenQ[#], #/2, 3 # + 1] &, n, # > 1 &]; Table[c = Collatz[n]; Length[c] - Position[c, Max[c]][[1, 1]], {n, 100}] (* _T. D. Noe_, Feb 27 2013 *)
%Y Cf. A006577, A220421.
%K nonn
%O 1,3
%A _Jayanta Basu_, Feb 27 2013
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