#include <bits/stdc++.h>
const long long mod = 1e9 + 7;
using namespace std;
const long long N = 1e5 + 5;
long long n;
long long a[N];
void fuck() {
  cin >> n;
  long long times = 0;
  for (long long i = 4 * n; i >= 0; i -= 2) {
    cout << i << ' ';
    times++;
    if (times == n) {
      break;
    }
  }
  cout << "\n";
  ;
  return;
}
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  long long t = 1;
  cin >> t;
  while (t--) {
    fuck();
  }
  return 0;
}
