#include <bits/stdc++.h>
using namespace std;
int main() {
  int t;
  cin >> t;
  while (t--) {
    int n;
    cin >> n;
    int k = n;
    n *= 4;
    int lol = 0;
    for (int i = n - 2; i >= 1; i -= 2) {
      if (lol == k) {
        break;
      } else {
        cout << i << " ";
        lol++;
      }
    }
    cout << endl;
  }
}
