#!/bin/python

import sys


q = int(raw_input().strip())
for a0 in xrange(q):
    len_i,c = raw_input().strip().split(' ')
    len_i,c = [int(len_i),int(c)]
    # your code goes here
    n = len_i -1
    temp = []
    lst = [i for i in range(1,len_i+1)]
    lst.sort(reverse=True)
    max_comparation = (n*(n+1))/2
    if max_comparation < c:
        print -1
    elif max_comparation == c:
        res =""
        for i in range(len(lst)):
            res += str(lst[i]) + " "
        print res    
        
    else:
        i = 0
        while c < max_comparation:
            n -=1
            temp.append(lst[i])
            lst.pop(i)
            max_comparation = 1+(n*(n+1))/2
            i += 1
        res = ""
        for i in range(len(lst)):
            res += str(lst[i]) + " "
        for j in range(len(temp)-1,-1,-1):
            res += str(temp[j]) + " "
        
        print res