#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  while (n--) {
    int x;
    cin >> x;
    for (int i = 4 * x, j = 1; j <= x; i -= 2) {
      j++;
      cout << i << " ";
    }
    cout << endl;
  }
  return 0;
}
