#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <string>
using namespace std;

#define For(i,n)	for (int i = 0; i<n;i++ )
#define For1(i,a,n)	for (int i = a; i<n;i++ )

int main(){
    int q;
    cin >> q;
    For(Q,q){
        int n,c;
        cin >> n >> c;
        vector<int> a(n);
        
        a[n/2]=1;
        int k=2;
        For1(i,1,n){
            if((n/2 -i) >=0) a[n/2-i]=k,k++;
            if((n/2 +i) < n) a[n/2+i]=k,k++;
        }
        
        int s=0;
        for(int i=n;i>0; i=i-2){
            s+=i-1;
            //cout<<i<<" "<<i-1<<" "<<s<<endl;
        }
        if(s==c)
            {
            For(i,n)cout<<a[i]<<" ";cout<<endl;
        }
        else cout<<-1<<endl;
        
        
        // your code goes here
    }
    return 0;
}