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();
            if(c>(len*(len-1)/2) )
                {
                System.out.print(-1);
            }
            else
            {int ar[]=new int[len+1];
            
            int x=(len*(len-1))/2-c;
           
            int pos=1;
            int n=1;
            while(pos<=len&&x!=0)
                {
                    ar[pos]=n+1;
                pos++;
                if(pos<=len)
                {ar[pos]=n;
                pos++;
                 n++;}
                n++;
                x--;
            }
            for(int i=pos;i<=len;i++)
                {
                  ar[i]=n;
                n++;
            }
            for(int i=1;i<=len;i++)
                {
                System.out.print(ar[i]+" ");
            }}
            System.out.println();
        }
    }
}