#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
bool wrong = false;
int small(int n){
	if(n <= 1)
		return 0;
	int l = n/2;
	int r = n-1-l;
	return (n-1) + small(l) + small(r);
}
ll large(ll n){
	return n * (n-1) / 2;
}
vector<int> solve(int n, int c){
	if(large(n) < c){
		wrong = true;
		return {};
	}
	if(n == 0)
		return {};
	c -= (n-1);
//	cout << n << ' ' << c << '\n';
	vector<int> result;
	for(int i = 0; i <= n/2; ++i){
		if(i+1 <= n/2 && large(i+1) + large(n-2-i) >= c){
//			cout << i << ' ' << small(i+1) << ' ' << small(n-2-i) << ' ' << "later is fine\n";
			continue;
		}
		result.push_back(i+1);
		vector<int> l = solve(i,large(i));
		vector<int> r = solve(n-i-1,c-large(i));
		result.insert(result.end(),l.begin(),l.end());
		for(int &v : r)
			v += i+1;
		result.insert(result.end(),r.begin(),r.end());
		return result;
	}
	wrong = true;
	return {};
}
void print(vector<int> arr){
	for(int i = 0; i < arr.size(); ++i)
		printf("%d%c",arr[i]," \n"[i==arr.size()-1]);
}
int main(){
	int t;
	cin >> t;
	while(t--){
		wrong = false;
		int len,c;
		cin >> len >> c;
		vector<int> ans = solve(len,c);
		if(wrong)
			puts("-1");
		else
			print(ans);
	}
}