Problem
2020 AIME I Problem 9
Let S be the set of positive integer divisors of 20^9. Three numbers are chosen independently and at random with replacement from the set S and labeled a_1,a_2, and a_3 in the order they are chosen. The probability that both a_1 divides a_2 and a_2 divides a_3 is \tfrac{m}{n}, where m and n are relatively prime positive integers. Find m.
Leading zeroes must be inputted, so if your answer is 34, then input 034
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