Consider a random walk on an infinite two-dimensional triangular lattice, a part of which is shown in the figure below. if the probabilities of moving to any of

Consider a random walk on an infinite two-dimensional triangular lattice, a part of which is shown in the figure below. If the probabilities of moving to any of the nearest neighbour sites are equal, what is the probability that the walker returns to the starting position at the end of exactly three steps? 1 (d) (a) (216 18 36