#include<bits/stdc++.h>
using namespace std ;
#define ll long long
int main()
{
    ll n ;
    cin >> n ;
    while(n--)
    {
        ll a,b ;
        cin >> a >> b ;
        ll sum = 0 ;
        for(ll i = 1 ; i <= a ; i++)
        {
            if(i%2 == 0 )
                sum+= i ;
        }
        if(sum == b)
        {
            if(a %2 == 0)
            {
                for(ll i = a ; i>=1 ; i--)
                    cout << i << " " ;
                    cout << endl ;
            }
            else
            {
                for(ll i = a ; i >= 1 ; i--)
                {
                    if(i % 2 == 0 )
                        cout << i << " " ;

                }
                for(ll i = 1 ; i <= a ; i++)
                {
                    if(i % 2 == 1 )
                        cout << i << " " ;

                }
                cout << endl ;
            }
        }
        else
            cout << -1 << endl ;
    }
}