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%I #5 Apr 18 2013 18:22:33
%S 1,335,1249,2013,6557,6801,6803,7501,7505,10219,22633,25183,27075,
%T 31839,36633,36691,40985,45013,45027,45041,59365,61601,64577,64579,
%U 75179,75507,77267,86015,88465,88473,97059,97061,97069,97073,97075,97261,107903,108545
%N Odd numbers n for which the number of iterations to reach the largest equals number of iterations to reach 1 from the largest in Collatz (3x+1) trajectory of n.
%H T. D. Noe, <a href="/A224533/b224533.txt">Table of n, a(n) for n = 1..1000</a>
%t Collatz[n_] := NestWhileList[If[EvenQ[#], #/2, 3*# + 1] &, n, # > 1 &]; Select[Range[1, 100000, 2], Position[Collatz[#], Max[Collatz[#]]] == {{(Length[Collatz[#]] + 1)/2}} &]
%Y Cf. A224303.
%K nonn
%O 1,2
%A _T. D. Noe_, Apr 14 2013