Stepping numbers
Source: Centroamerican and Caribbean Math Olympiad 2023, P2
July 25, 2023
number theoryOMCCblackboardOperation
Problem Statement
Octavio writes an integer on a blackboard and then he starts a process in which, at each step he erases the integer written on the blackboard and replaces it with one of the following numbers:
3k-1, 2k+1, \frac{k}{2}.
provided that the result is an integer.Show that for any integer , Octavio can write on the blackboard the number after a finite number of steps.