MathDB

Let

x

and

y

be positive integers we have a table

x\times y

where

(x + 1)(y + 1)

points are red(the points are the vertices of the squares). Initially there is one ant in each red point, in a moment the ants walk by the lines of the table with same speed, each turn that an ant arrive in a red point the ant moves

90º

to some direction. Determine all values of

x

and

y

where is possible that the ants move indefinitely where can't be in any moment two ants in the same red point.

Problem Statement