#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <array>
using namespace std;
vector<int> lena_sort(vector<int> nums, int* com) {
    
    if (nums.size() == 1) {
        return nums;
    }
    
   int pivot = nums[0];
    vector<int> less;
    vector<int> more;
    for (int i = 1; i < nums.size()&&(*com!=0); ++i) {
    	// Comparison
        
        if (nums[i] < pivot) {
            less.push_back(nums[i]);
            com--;
            
        }
        else {
            more.push_back(nums[i]);
            com--;
        }
    }
    int com1;
    com1 = *com;
    vector<int> sorted_less = lena_sort(less, &com1);
    vector<int> sorted_more = lena_sort(more, &com1);
    vector<int> ans;
    ans.insert(ans.end(),sorted_less.begin(),sorted_less.end());
    ans[ans.size()]=pivot;
    ans.insert(ans.end(),sorted_more.begin(),sorted_more.end());
    
    return ans;
}

int main() {
   int q;
    cin>>q;
    for(int i=0; i<q; i++)
        {
      
        int n;
        int comp;
        cin>>n>>comp;
        int max=n*log2(n);
        if(comp>max)
            cout<<-1<<endl;
        else
            {
            
            vector<int> num(n);
            for(int j=1;j<=n; j++)
                num[j-1]=n-j+1;
            vector<int> ans;
            ans=lena_sort(num, &comp);
            for(int k=0; k<n; k++)
                cout<<ans[k]<<" ";
            cout<<endl;
        }
    }
    return 0;
}