import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

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();
			// your code goes here

			int perm = getperm(len);
			if (len == 1) {
				System.out.println(1);
			}else if (c == perm) {
				String s="";
				for(int i=len; i>0; i--){
					s = s+ i +" ";
				}
				System.out.println(s);
				
			} else if (c > perm || c < len - 1) {
				System.out.println(-1);
			} else {
				findSol(len, c);
			}

		}
	}

	private static void findSol(int len, int c) {
		String sol = "";
		List<Integer> alreadyIn = new ArrayList<>();
		int count = 0;
		for (int i = len-1; i > 0; i--) {
			if (count + i <= c) {
				count = count + i;
				alreadyIn.add(i);
			}
			if (count == c) {
				break;
			}
		}

		for (Integer i : alreadyIn) {
			sol = sol + i + " ";
		}

		for (int i = 1; i <= len; i++) {
			if (!alreadyIn.contains(i)) {
				sol = sol + i + " ";
			}

		}

		System.out.println(sol);
	}

	private static int getperm(int q) {
		int prem = 0;
		for (int i = 1; i < q ; i++) {

			prem = prem + i;
		}

		return prem;
	}

}