67. A digital game is played between two very smart students, A and B. The referee first writes the positive integers $2,3, \cdots \cdots, 2020$ on the blackboard, then randomly erases one number. Next, A and B take turns erasing one of the numbers (B erases a number first, then A erases a number), and so on. If the last two remaining numbers are coprime, A wins; otherwise, B wins. According to this game rule, the probability of A winning is
Answer: $\frac{1010}{2019}$