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

public class Cupcakes {

	public static int lenaSort(int a[], int count){
		if(a.length<=1){
			return a.length;
		}
		int pivot = a[0];
        
        //System.out.println("pivot:"+pivot);
        int lessc=0;
        int morec=0;
        for(int i=1;i<a.length;i++){
        	if(a[i]>pivot){
        		morec++;
        	}
        	else if(a[i]<pivot){
        		lessc++;
        	}
        	
        }
        
        int less[] = new int[lessc];
        int more[] = new int [morec];
        if(lessc>0){
        count = count + lessc -1;
        }
        if(morec>0){
            count = count + morec -1;
        }    
        int k=0;
        int j=0;
        for(int i=1;i<a.length;i++){
        	if(a[i]>pivot){
        	   more[k]=a[i];
        	   k++;
        	}
        	else if(a[i]<pivot){
        		less[j]=a[i];
        		j++;
        	}
        }
        	
        
        int sortedless =lenaSort(less,count);
        //System.out.println(sortedless);
        int sortedmore =lenaSort(more,count);
        //System.out.println(sortedmore);
        //int ans = sortedless + pivot + sortedmore;
        return count;    
	}
    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 a[] = new int[len];
            
            for(int i=0;i<len;i++){
            	Random rand = new Random();

            	int  n = rand.nextInt(50) + 1;
                a[i]=n;
            }
            
          //  System.out.println("random array");
            //for(int g=0;g<a.length;g++)	{
            	//System.out.print(a[g]+" ");
            //}//
            
            int f = lenaSort(a,0);
            //System.out.println("final:"+f);
            if(f==c){
               for(int g=0;g<a.length;g++)	{
            	System.out.print(a[g]+" ");
                } 
            }
            else{
                System.out.println("-1");
            }
            
            
            
            
            
            
        }
    }
}