MathDB

6

Part of 2015 Thailand Mathematical Olympiad

Problems(1)

no of ways to fill {-2, -1, 1, 2} in m x n table , each product is -2

Source: Thailand Mathematical Olympiad 2015 p6

8/16/2020
Let mm and nn be positive integers. Determine the number of ways to fill each cell of an m×nm \times n table with a number from {−2,−1,1,2}\{-2, -1, 1, 2\} so that the product of the numbers written in each row and column is −2-2.
combinatorics