import java.io.*;
	import java.util.*;
	import java.text.*;
	import java.math.*;
	import java.util.regex.*;
	
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==0){
	            	if(len==1){
	            		System.out.println(1);
	            	}else
	            	{
	            		System.out.println(-1);
	            	}
	            }else if(len==1 && c>1){
                    System.out.println(-1);
                }else if(len==2 && c==1){
                    System.out.println("1 2");
                }
                else if(len==3 && c==3){
                    for(int i=1;i<=len;i++){
                        System.out.print(i+" ");
                    }
                    System.out.println();
                }else if(len==3 && c==2){
                    System.out.println("2 1 3");
                }
	            else if(c== len*(len-1)/2){
	            	for(int i=len;i>=1;i--){
	            		System.out.print(i+" ");
	            	}
	            	System.out.println();
	            }else if(c>len*(len-1)/2){
	            	System.out.println(-1);
	            }else if(c<len-1){
	            	System.out.println(-1);
	            }else{
                    if(len%2==0){
                       for(int i=len;i>=2;i=i-2){
	            		System.out.print(i+ " ");
	            	    }
                        System.out.print(1+" ");
                        for(int i=3;i<=len-1;i=i+2){
                            System.out.print(i+ " ");
                        }
                     }else{
                      for(int i=len-1;i>=2;i=i-2){
	            		System.out.print(i+ " ");
	            	}
                        
                        System.out.print(1+" ");
	            	for(int j=3;j<=len;j=j+2){
	            		System.out.print(j+ " ");
	            	}   
                    }
	            	
	            	System.out.println();
	            }
	            
	        }
	    }
	}