consider a chess knight moving on the first quadrant of the plane.It starts at (0,0) and at each step it will move two units in one direction and one unit in the other,such that x>=0 and y>=0.At each step the knight randomly selects a valid move with uniform probability.

After n moves,what is the expected euclidean distance of the knight from the origin? How to solve this kind of problem?Pleas I need help.