A198588 Odd numbers producing 5 odd numbers in the Collatz iteration.

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

Author

T. D. Noe, Oct 31 2011

Keywords

• nonn

Links

• Vincenzo Librandi and T. D. Noe, Table of n, a(n) for n = 1..900 (terms 1 to 128 from Vincenzo Librandi)

Crossrefs

Cf. A198584.

Programs

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