#!/bin/python

import sys


q = int(raw_input().strip())
for a0 in xrange(q):
    n,c = map(int, raw_input().strip().split(' '))
    # your code goes here
    max_comp = n*(n-1)/2
    if c > max_comp:
        print '-1'
        continue
    elif c == max_comp:
        for i in range(n,1,-1):
            print i,
        print i
    elif c < max_comp:
        arr = []
        comp = max_comp - c
        a = n-2
        count = 1
        while a != comp:
            a+= a-2
            count += 1
        for i in range(n,0,-1):
            arr.append(i)
        arr1 =[]
        for j in range(0, 2*count, 2):
            #print arr,arr[j]
            arr1.append(arr[j])
        for j in arr1:
            arr.remove(j)
            
        #print arr, arr1,n
        arr1.sort()
        final = arr + arr1
        for i in range(n):
            if i==n-1:
                print final[i]
            else:
                print final[i],