#include<bits/stdc++.h>
using namespace std;
#define int long long
#define endl '\n'
#define io ios::sync_with_stdio(false),cin.tie(0),cout.tie(0)
#define all(a) a.begin(),a.end()
typedef pair<int,int> PII;
typedef long long LL;
const int N = 1e6;
const int mod = 998244353;
inline int ls(int x) { return x << 1; }
inline int rs(int x) { return x << 1 | 1; }
int dx[8] = { 1,0,0,-1,-1,-1,1,1 };
int dy[8] = { 0,-1,1,0,-1,1,-1,1};
inline int gcd(int a, int b)
{
   if (b) while ((a %= b) && (b %= a));
   return a + b;
}
int vis[N + 5];
void solve()
{
    int n;
    cin >> n;
    if(n == 2){
        cout << "1 0" << endl;
        return;
    }
    if(n == 3){
        cout << "1 0 2" << endl;
        return;
    }
    if(vis[n]){
        cout << "impossible" << endl;
        return;
    }
    cout << "1 0 2 4 3 ";
    int now = 5;
    while(now < n){
        if(vis[now + 1]){
            cout << now + 1 << ' ' << now << ' ';
            now += 2;
        }
        else {
            cout << now << ' ';
            now++;
        } 
    }
    cout << endl;
    
}
signed main()
{
    io;
    int tt = 1;
    int now = 1;
    while(now <= N){
        vis[now] = 1;
        now *= 2;
    }
    cin >> tt;
    while(tt--)
    {
        solve();
    }
	return 0;
}