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

1,1

Links

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

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 *)

Crossrefs

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

Sequence in context: A229608 A185061 A129198 * A225258 A162613 A120858

Adjacent sequences: A122439 A122440 A122441 * A122443 A122444 A122445

Keyword

nonn

Author

T. D. Noe, Sep 06 2006

Status

approved