Dropping times of odd numbers in the 3x+1 problem (or the Collatz problem).
2, 4, 2, 7, 2, 5, 2, 7, 2, 4, 2, 5, 2, 59, 2, 56, 2, 4, 2, 8, 2, 5, 2, 54, 2, 4, 2, 5, 2, 7, 2, 54, 2, 4, 2, 51, 2, 5, 2, 8, 2, 4, 2, 5, 2, 45, 2, 8, 2, 4, 2, 42, 2, 5, 2, 31, 2, 4, 2, 5, 2, 8, 2, 15, 2, 4, 2, 7, 2, 5, 2, 7, 2, 4, 2, 5, 2, 40, 2, 21, 2, 4, 2, 29
1
This is similar to A126241, but without the even terms. See S000259 for a more restrictive version.
T. D. Noe, Plot of 10000 terms
T. D. Noe, Table of 10000 terms
(Mma) Table[cnt = 1; m = n; While[If[EvenQ[m], m = m/2, m = (3*m + 1)/2]; m > n, cnt++]; cnt, {n, 1, 199, 2}]
Cf. A126241, S000261 (Collatz applied to 2^n-1).
nonn
T. D. Noe, Sep 17 2014