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

public class Solution {
    
    static int counter = 0;

    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();
            // your code goes here
            int cond = (len*(len-1))/2;
			if(cond<c){
				System.out.println(-1);
			}else{
				int[] aaa = IntStream.rangeClosed(1,len).boxed()
					.mapToInt(Integer::intValue).toArray();
				
				int[] res = lena_sort(aaa, c);
				Arrays.stream(res).forEach(a -> System.out.print(a + " "));
				System.out.println();
			}
        }
    }
    
    public static int[] lena_sort(int[] nums, int q) {
		if (nums.length <= 1) {
			return nums;
		}
		int pivot = nums[0];
		List<Integer> less = new ArrayList<>();
		List<Integer> more = new ArrayList<>();
		for (int i = 1; i < nums.length; ++i) {
			// Comparison
			if (nums[i] < pivot) {
				less.add(0, nums[i]);
			} else {
				more.add(0, nums[i]);
			}
			counter++;
			if (counter >= q) {
				break;
			}
		}
		int[] sorted_less = lena_sort(less.stream().mapToInt(Integer::intValue).toArray(), q);
		int[] sorted_more = lena_sort(more.stream().mapToInt(Integer::intValue).toArray(), q);

		int[] total = new int[sorted_less.length + sorted_more.length + 1];
		System.arraycopy(sorted_less, 0, total, 0, sorted_less.length);
		total[sorted_less.length] = pivot;
		System.arraycopy(sorted_more, 0, total, sorted_less.length + 1, sorted_more.length);

		return total;
	}
}