A226631 Length of the shortest primitive cycle(s) of positive integers under iteration by the 3x-k function, where k=A226630(n).

1, 4, 6, 17, 19, 34, 12, 9, 5, 22, 12, 17, 17, 69, 7, 18, 22, 38, 11, 12, 6, 68, 44, 30, 9, 19, 68, 14, 22, 44, 23, 30, 84, 8, 17, 17, 30, 12, 68, 18, 7, 22, 15, 22, 85, 10, 14, 22, 22, 10, 14, 18, 44, 12, 68, 22, 9, 38, 17, 14, 55, 8, 56, 50, 36, 44, 25, 37

Offset: 1

Author

Geoffrey H. Morley, Jun 14 2013

Keywords

• nonn

Comments

A cycle is called primitive if its elements are not a common multiple of the elements of another cycle.

The 3x-k function T_k is defined by T_k(x) = x/2 if x is even, (3x-k)/2 if x is odd.

Links

• Geoffrey H. Morley, Table of n, a(n) for n = 1..600

Formula

a(n) = min_{j=A226628(n) to A226628(n+1)-1} A226625(j).