Leetcode 3336. Find the Number of Subsequences With Equal GCD

Count the number of ordered pairs of disjoint non-empty subsequences (seq1, seq2) of nums whose elements have the same GCD, returning the result modulo 10^9+7 (n ≤ 200, nums[i] ≤ 200). The core challenge is to aggregate subsequences by their GCD (bounded by 200) and combine those counts efficiently to count disjoint pairs.