login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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
Sequence in context: A225055 A341194 A120947 * A046793 A182940 A101278
KEYWORD
nonn
AUTHOR
T. D. Noe, Mar 04 2013
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 28 14:38 EDT 2024. Contains 371254 sequences. (Running on oeis4.)