

A222600


Least number k such that the difference between the number of halving and tripling steps in the Collatz (3x+1) iteration is n.


1



1, 2, 4, 3, 6, 12, 7, 9, 18, 25, 33, 43, 39, 78, 105, 135, 123, 169, 159, 295, 283, 111, 222, 297, 175, 103, 91, 121, 31, 27, 54, 73, 97, 129, 171, 231, 313, 411, 543, 327, 649, 859, 763, 1017, 1351, 1215, 703, 937, 871, 1161, 2223, 3097, 2631, 3567, 3175, 4233
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

0,2


COMMENTS

This is the first number in row n of A222599.


LINKS

T. D. Noe, Table of n, a(n) for n = 0..264 (searching until the Collatz sequence has a term greater than 2^63)


MATHEMATICA

Collatz[n_] := NestWhileList[If[EvenQ[#], #/2, 3 # + 1] &, n, # > 1 &]; nn = 50; t = Table[0, {nn}]; n = 0; While[Min[t] == 0, n++; c = Collatz[n]; e = Select[c, EvenQ]; diff = 2*Length[e]  Length[c]; If[diff < nn  1 && t[[diff + 2]] == 0, t[[diff + 2]] = n]]; t


CROSSREFS

Cf. A213678, A222599.
Sequence in context: A225055 A341194 A120947 * A046793 A182940 A101278
Adjacent sequences: A222597 A222598 A222599 * A222601 A222602 A222603


KEYWORD

nonn


AUTHOR

T. D. Noe, Mar 04 2013


STATUS

approved



