#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  int t;
  cin >> t;
  while (t--) {
    int num, i, cnt = 0;
    cin >> num;
    for (i = 4 * num;; i--) {
      if (i % 2 == 0) {
        cout << i << " ";
        cnt++;
        if (cnt == num) break;
      }
    }
    cout << "\n";
  }
}
