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Least k such that the Collatz (3x+1) iteration starting with k has "dropping time" A122437(n).
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%I #9 Apr 20 2024 10:27:17

%S 2,5,3,11,7,39,287,231,191,127,359,511,239,159,639,283,991,251,167,

%T 111,1695,1307,871,927,671,155,103,1639,91,3431,3399,2287,71,6395,47,

%U 31,2047,27,1819,17691,6887,4591,13439,6383,4255,7963,7527,12399,7279,1583

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

%H T. D. Noe, <a href="/A122442/b122442.txt">Table of n, a(n) for n = 1..130</a>

%t 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 *)

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

%K nonn

%O 1,1

%A _T. D. Noe_, Sep 06 2006