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 n = in.nextInt();
            int c = in.nextInt();
            if(c>n*(n-1)/2 || c<(n*n-1)/4)
            System.out.println("-1");
            else
            {
                int a[]=new int[n];
                int pos=0,k=1;
                int x=n*(n-1)/2-c;
                while(x!=0)
                {
                    if(pos+1<n)
                    a[pos+1]=k;
                    if(pos<n)
                    a[pos]=k+1;
                    pos+=2;
                    k+=2;
                    x--;
                }
                for(int i=pos;i<n;i++)
                {
                    a[i]=k;
                    k++;
                }
                for(int i=0;i<n;i++)
                    System.out.print(a[i]+" ");
                System.out.println();
            }    
            // your code goes here
        }
    }
}