CF1884D Counting Rhyme
Description
You are given an array of integers $ a_1, a_2, \ldots, a_n $ .
A pair of integers $ (i, j) $ , such that $ 1 \le i < j \le n $ , is called good, if there does not exist an integer $ k $ ( $ 1 \le k \le n $ ) such that $ a_i $ is divisible by $ a_k $ and $ a_j $ is divisible by $ a_k $ at the same time.
Please, find the number of good pairs.
Input Format
Each test contains multiple test cases. The first line contains the number of test cases $ t $ ( $ 1 \le t \le 2 \cdot 10^4 $ ). The description of the test cases follows.
The first line of each test case contains a single integer $ n $ ( $ 1 \le n \le 10^6 $ ).
The second line of each test case contains $ n $ integers $ a_1, a_2, \ldots, a_n $ ( $ 1 \le a_i \le n $ ).
It is guaranteed that the sum of $ n $ over all test cases does not exceed $ 10^6 $ .
Output Format
For each test case, output the number of good pairs.
Explanation/Hint
In the first test case, there are no good pairs.
In the second test case, here are all the good pairs: $ (1, 2) $ , $ (2, 3) $ , and $ (2, 4) $ .