import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int q = in.nextInt();
        
        while(q-->0)
            {
            int n=in.nextInt();
            int c=in.nextInt();
            
            int a[]=new int[n];
            
            for(int i=0;i<n;i++)
                a[i]=i+1;
            
            if(c>(n*(n-1))/2)
                System.out.println("-1");
            
            else
                {
                int i=0;
                
                while(c>0)
                    {
                    int temp=a[i+1];
                    a[i+1]=a[i];
                    a[i]=temp;
                    
                    i++;
                    i=i%n;
                    c-=2;
                }
                
                for(int j=0;j<n;j++)
                    System.out.print(a[j]+" ");
                
                System.out.println();
            }
        }
    }
}