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D - Index Trio /

Time Limit: 2 sec / Memory Limit: 1024 MB

### 問題文

• 1 \leq i, j, k \leq N
• \frac{A_i}{A_j} = A_k

### 制約

• 1 \leq N \leq 2 \times 10^5
• 1 \leq A_i \leq 2 \times 10^5 \, (1 \leq i \leq N)
• 入力は全て整数

### 入力

N
A_1 \ldots A_N


### 入力例 1

3
6 2 3


### 出力例 1

2


(i, j, k) = (1, 2, 3), (1, 3, 2) が条件を満たします。

### 入力例 2

1
2


### 出力例 2

0


### 入力例 3

10
1 3 2 4 6 8 2 2 3 7


### 出力例 3

62


Score : 400 points

### Problem Statement

You are given an integer sequence A = (A_1, \dots, A_N) of length N.

Find the number of triplets of integers (i, j, k) satisfying all of the conditions below.

• 1 \leq i, j, k \leq N
• \frac{A_i}{A_j} = A_k

### Constraints

• 1 \leq N \leq 2 \times 10^5
• 1 \leq A_i \leq 2 \times 10^5 \, (1 \leq i \leq N)
• All values in input are integers.

### Input

Input is given from Standard Input in the following format:

N
A_1 \ldots A_N


### Sample Input 1

3
6 2 3


### Sample Output 1

2


(i, j, k) = (1, 2, 3), (1, 3, 2) satisfy the conditions.

### Sample Input 2

1
2


### Sample Output 2

0


### Sample Input 3

10
1 3 2 4 6 8 2 2 3 7


### Sample Output 3

62