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A222562
Numbers that are highest in their respective Collatz (3x+1) trajectories only.
5
1, 2, 4, 8, 20, 24, 32, 48, 56, 68, 72, 80, 84, 96, 104, 116, 128, 132, 144, 152, 168, 176, 180, 192, 200, 212, 224, 228, 240, 260, 264, 272, 276, 288, 296, 308, 312, 320, 324, 336, 344, 356, 360, 368, 372, 384, 392, 404, 408, 416, 452, 456, 464, 468, 480, 488
OFFSET
1,2
COMMENTS
This is effectively the complement of A176869 in A033496, excluding numbers which are also highest in trajectories less than the number itself.
MATHEMATICA
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 *)
CROSSREFS
Sequence in context: A217520 A124154 A296606 * A252891 A102634 A026520
KEYWORD
nonn
AUTHOR
Jayanta Basu, Feb 27 2013
STATUS
approved