A198589 Odd numbers producing 6 odd numbers in the Collatz iteration.

7, 15, 29, 61, 117, 241, 245, 267, 469, 483, 497, 535, 537, 965, 981, 985, 995, 1069, 1073, 1075, 1877, 1933, 1969, 1971, 1989, 2009, 2141, 2147, 2149, 3861, 3925, 3939, 3941, 3981, 4017, 4019, 4043, 4277, 4293, 4297, 4301, 7509, 7733, 7877, 7885, 7957, 8035

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..1000 (terms 1 to 282 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]] == 6, AppendTo[t, n]], {n, 1, 10000, 2}]; t