#include <bits/stdc++.h>

using namespace std;

unsigned long long lena_sort(vector<int>& nums) {
    if (nums.size() < 2) {
        return 0;
    }
    int pivot = nums[0];
    vector<int> less;
    vector<int> more;
    unsigned long long counter = 0;
    for (int i = 1; i < nums.size(); ++i) {
        // Comparison
        ++counter;
        if (nums[i] < pivot) {
            less.push_back(nums[i]);
        }
        else {
            more.push_back(nums[i]);
        }
    }

    unsigned long long c1 = lena_sort(less);
    unsigned long long c2 = lena_sort(more);
    for (int i = 0; i < nums.size(); ++i) {
        if (i < less.size())
            nums[i] = less[i];
        else if (i == less.size())
            nums[i] = pivot;
        else if (i - less.size() < more.size())
            nums[i] = more[i - less.size() - 1];
    }
    return c1 + c2 + counter;
}

int main(){
    int q;
    cin >> q;
    for(int a0 = 0; a0 < q; a0++){
        int len;
        int c;
        cin >> len >> c;

        // your code goes here
        vector<int> data(len, 0);
        int k = 0;
        for (int i = len/2; i >=0; i -= 1) {
            data[k] = 2*i;
            data[len - k - 1] = 2*i + 1;
            ++k;
        }
        
        auto orig = data;
        unsigned long long minVal = lena_sort(data);
        if (c == minVal) {
            for (int v : orig)
                cout << v << " ";
            cout << "\n";
            continue;
        }
        unsigned long long maxVal = lena_sort(data);
        if (c > maxVal || c < minVal)
            cout << -1 << "\n";
        if (c == maxVal) {
            for (int v : data)
                cout << v << " ";
            cout << "\n";
        }
    }
    return 0;
}