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A198588
Odd numbers producing 5 odd numbers in the Collatz iteration.
1
11, 23, 45, 93, 181, 201, 369, 373, 401, 403, 725, 739, 753, 803, 805, 1477, 1493, 1507, 1605, 1611, 1613, 2901, 2957, 3013, 3033, 3213, 3221, 3223, 5909, 5973, 6029, 6065, 6067, 6421, 6445, 6453, 6465, 11605, 11829, 12053, 12131, 12133, 12853, 12885, 12893
OFFSET
1,1
LINKS
Vincenzo Librandi and T. D. Noe, Table of n, a(n) for n = 1..900 (terms 1 to 128 from Vincenzo Librandi)
MATHEMATICA
Collatz[n_] := NestWhileList[If[EvenQ[#], #/2, 3 # + 1] &, n, # > 1 &]; t = {}; Do[If[Length[Select[Collatz[n], OddQ]] == 5, AppendTo[t, n]], {n, 1, 20000, 2}]; t
CROSSREFS
Cf. A198584.
Sequence in context: A146451 A195043 A029468 * A334829 A354589 A068231
KEYWORD
nonn
AUTHOR
T. D. Noe, Oct 31 2011
STATUS
approved