login
Record number of steps to reach 1 in '3x+1' problem, corresponding to starting values in A006877 (same as A006878 except here we start counting at 1 instead of 0).
9

%I #30 Jun 15 2019 10:26:11

%S 1,2,8,9,17,20,21,24,112,113,116,119,122,125,128,131,144,145,171,179,

%T 182,183,209,217,238,262,268,276,279,282,308,311,324,340,351,354,375,

%U 383,386,443,449,470,509,525,528,531,557,560,563,584,597,613,665,686

%N Record number of steps to reach 1 in '3x+1' problem, corresponding to starting values in A006877 (same as A006878 except here we start counting at 1 instead of 0).

%C Both the 3x+1 steps and the halving steps are counted.

%D R. E. Maeder, Programming in Mathematica, 3rd Edition, Addison-Wesley, pages 251-252.

%H T. D. Noe, <a href="/A033492/b033492.txt">Table of n, a(n) for n=1..130</a> (from Eric Roosendaal's data)

%H Eric Roosendaal, <a href="http://www.ericr.nl/wondrous/delrecs.html">3x+1 Delay Records</a>

%H <a href="/index/3#3x1">Index entries for sequences related to 3x+1 (or Collatz) problem</a>

%Y Equal to A006878 + 1. Cf. A006884, A006885, A033492.

%K nonn

%O 1,2

%A _Jeff Burch_

%E Corrected and extended by Lee Corbin (lcorbin(AT)tsoft.com)

%E More terms from Larry Reeves (larryr(AT)acm.org), Apr 27 2001