Conditional mutual information. Consider a sequence of n binary random variables X1, X,…,Xn. Each sequence with an even number of 1’s has probability 2−(n−1) , and each sequence with an odd number of 1’s has probability 0. Find the mutual informations I (X1; X2), I (X2; X3|X1), . . . , I (Xn−1; Xn|X1,…,Xn−2).