Problem

Source: 239 2017 J6

Tags: combinatorics, blackboard



The natural numbers $y>x$ are written on the board. Vassya decides to write the reminder of one number on the board to some other non-zero number in each step. Prove that Vassya can find a natural number $k$ such that if $y>k$ then the number distinct numbers on the board after arbitrary number of steps does not exceed $\frac{y}{1000000}.$