For the events A1, A2, and A3 in the same sample space, it is known that P(Ai) = 1 2i , i = 1, 2, 3, and P(AiAi+1) = 1 2i+2 , i = 1, 2.

If, in addition, we know that the events A1 and A3 are mutually exclusive, calculate the probability that at least one of A1, A2, A3 occur.