A122442 Least k such that the Collatz (3x+1) iteration starting with k has "dropping time" A122437(n).

2, 5, 3, 11, 7, 39, 287, 231, 191, 127, 359, 511, 239, 159, 639, 283, 991, 251, 167, 111, 1695, 1307, 871, 927, 671, 155, 103, 1639, 91, 3431, 3399, 2287, 71, 6395, 47, 31, 2047, 27, 1819, 17691, 6887, 4591, 13439, 6383, 4255, 7963, 7527, 12399, 7279, 1583

Offset: 1

Author

T. D. Noe, Sep 06 2006

Keywords

• nonn

Links

• T. D. Noe, Table of n, a(n) for n = 1..130

Crossrefs

Cf. A122437 (allowable "dropping times" of the Collatz iteration).

Programs

Mathematica

With[{s = 1 + Log2[3]}, {2}~Join~Table[(k = 3; While[-1 + Length@ NestWhileList[If[EvenQ[#], #/2, 3 # + 1] &, k, # >= k &] != m, k += 2]; k), {m, Array[Floor[1 + s*#] &, 50]}] ] (* Michael De Vlieger, Apr 19 2024 *)