You do not need to be able to play chess to solve this problem.
The standard move for a knight on a chess board is 2 steps in one direction and one step in the other direction. A knight's tour is a sequence of moves in which the knight visits every square on the board once and only once and a circuit is a tour in which the knight returns to the starting point. Prove that a knight cannot make a tour on a 2 by board for any value of .
Prove that a knight cannot make a circuit on a 3 by 4 rectangular board.