254. Factor Combinations

Numbers can be regarded as the product of their factors.

• For example, 8 = 2 x 2 x 2 = 2 x 4.

Given an integer n, return all possible combinations of its factors. You may return the answer in any order.

Note that the factors should be in the range [2, n - 1].

Example 1:

Input: n = 1
Output: []

Example 2:

Input: n = 12
Output: [[2,6],[3,4],[2,2,3]]

Example 3:

Input: n = 37
Output: []

Constraints:

• 1 <= n <= 107