Hi everyone,
I’m trying to solve this problem. I know it’s a kind of dynamic programming problem, but I still don’t get the way to do it. Please help me! I really appreciate your time! Thank you in advance!
Given a list. Each element in this list is a sequence of N numbers in lexicographical order such that:

The i_th number can have a value up to 2 * i.

For all j > i, the j_th number is always greater than the i_th number.
Find the x_th element in that list.
Example:
N = 2, we have the following list:
1 2
1 3
1 4
2 3
2 4
The 4th element is 2 3