Let n be a positive integer. Nancy is given a rectangular table in which each entry is a positive integer. She is permitted to make either of the following two moves:
(1) select a row and multiply each entry in this row by n;
(2) select a column and subtract n from each entry in this column.
Find all possible values of n for which the following statement is true:
Given any rectangular table, it is possible for Nancy to perform a finite sequence of moves to create a table in which each entry is 0. geometryrectanglecombinatorics unsolvedcombinatorics