// Author: Donomonayuas

#include <bits/stdc++.h>

#define rep(i, j, k) for (int i = (j); i <= (k); ++i)
#define per(i, j, k) for (int i = (j); i >= (k); --i)
#define SZ(v) int((v).size())
#define ALL(v) (v).begin(),(v).end()
#define fi first
#define se second
using ll = long long;
using pii = std::pair<int, int>;
using pll = std::pair<ll, ll>;

template<class T> inline void chkmn(T &x, T y) { if (y < x) x = y; }
template<class T> inline void chkmx(T &x, T y) { if (y > x) x = y; }

using namespace std;

const int maxn = 1010;

int n, a[maxn], b[maxn], ans[maxn];

void work() {
  cin >> n;
  rep (i, 1, n) a[i] = 3 * (n - 1) - i + 1;
  rep (i, 1, n) b[i] = i - 1;
  if (n & 1) {
    int pos = 2;
    rep (i, 1, n / 2) ans[i] = b[pos], pos += 2;
    pos = 1;
    rep (i, n / 2 + 2, n) ans[i] = b[pos], pos += 2;
    ans[n / 2 + 1] = 2 * n - 3;
  } else {
    int pos = 2;
    rep (i, 1, n / 2) ans[i] = b[pos], pos += 2;
    pos = 1;
    rep (i, n / 2 + 1, n) ans[i] = b[pos], pos += 2;
  }
  rep (i, 1, n) cout << a[i] << " " << ans[i] << ' ';
  cout << '\n';
}

int main() {
  cin.tie(nullptr) -> ios::sync_with_stdio(false);
  int t; cin >> t;
  while (t--) work();
}