MathDB
reversing row/column of number table

Source: Yugoslav TST 1997 P3

May 15, 2021
combinatorics

Problem Statement

Numbers 1,2,,199721,2,\ldots,1997^2 are written in the cells of a 1997×19971997\times1997 table. It is allowed to apply the following transformations: exchange places of any two rows or any two columns, or reverse a row or column. (When a row or column is reversed, the first and last entry exchange their positions, so do the second and second last, etc.) Is it possible that, after finitely many such transformations, arbitrary two numbers exchange their positions and no other number changes its position?