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

public class Solution {
    static long count;
   public static ArrayList<Long> lena_sort(ArrayList<Long> nums, long c) {
        if (nums.size() <= 1) {
            return nums;
        }
       long pivot = nums.get(0);
       ArrayList<Long> less=new ArrayList<>() ;
       ArrayList<Long> more=new ArrayList<>() ;
        for (int i = 1; i < nums.size(); ++i) {
            // Comparison
            count++;
            if (nums.get(i) < pivot) {
                less.add(nums.get(i));
            }
            else {
                more.add(nums.get(i));
            }
        }
       ArrayList<Long> sorted_less = lena_sort(less,c);
       ArrayList<Long> sorted_more = lena_sort(more,c);
       ArrayList<Long> ans = new ArrayList<>();
       for(int i=0;i<sorted_less.size();i++)
           ans.add(sorted_less.get(i));
       ans.add(pivot);
       for(int i=0;i<sorted_more.size();i++)
            ans.add(sorted_more.get(i));
        return ans;
    }

    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();
            ArrayList<Long> nums=new ArrayList<>();
            for(int i=0;i<len;i++)
                nums.add(i,(long)(i+1));
            Collections.shuffle(nums);
            count=0;
            ArrayList<Long> ans=lena_sort(nums,c);
          //  nums.stream().forEach(System.out::println);
            if(ans.size()==1 && c==0)
                System.out.println(ans.get(0));
            else if(count!=c)
                System.out.println("-1");
            else{
                for(int i=0;i<nums.size();i++)
                    System.out.print(nums.get(i)+" ");
                System.out.println();
            }
            ans.clear();
        }
    }
}