Argentina MO 2021 National Level 2 P1
Source:
April 23, 2022
contestscoprime numbersnumber theory
Problem Statement
You have two blackboards and . You have to write on them some of the integers greater than or equal to and less than or equal to in such a way that each number on blackboard is co-prime with each number on blackboard Determine the maximum possible value of multiplying the number of numbers written in by the number of numbers written in .