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();
        for(int a0 = 0; a0 < q; a0++)
        {
            int len = in.nextInt();
            int c = in.nextInt();
            int lim=(len*(len-1))/2;
            //upper limit case
            if(c>lim)
                System.out.println("-1 ");
            else
            {              
                //case of len=1
                if(len==1)
                {
                    if(c==0)
                    System.out.println("1");
                    else
                    System.out.println("-1");
                }
                // case of len=2
                if(len==2)
                {
                   if(c==1)
                   System.out.println("1 2");
                   else
                       System.out.println("-1");
                }
                // case of len=3:
                if(len==3)
                {
                    if(c==2)
                         System.out.println("1 2 3");
                    else
                        System.out.println("-1");
                }
                // cse len=4:
                if(len==4)
                {
                    if(c==6)
                         System.out.println("1 2 3 4");
                    else if(c==5)
                        System.out.println("1 3 2 4");
                    else if(c==4)
                        System.out.println("2 1 3 4");
                    else
                       System.out.println("-1"); 
                }
                
                //next constraint on c
                if(c<len-1 && len>1  )
                    System.out.println("-1");
                else
                {
                if(len>4)
                {
                //array declare    
                int a[]=new int[len];
                for(int i=0;i<len;i++)
                {
                     a[i]=i+1;    
                }
                
                //print array:
                for(int i=0;i<len;i++)
                {
                     System.out.print(a[i]+" ");  
                }
                System.out.println();
                }
                }
                
            }
        }
    }
}