#include <bits/stdc++.h>
using namespace std;
int main() {
  int a;
  int t;
  cin >> t;
  while (t--) {
    cin >> a;
    for (int i = 4 * a; i > a * 2; i -= 2) {
      cout << i << " ";
    }
    cout << endl;
  }
  return 0;
}
