/******************************************
*    AUTHOR:         BHUVNESH JAIN        *
*    INSTITUITION:   BITS PILANI, PILANI  *
******************************************/
#include <bits/stdc++.h>
using namespace std;
 
typedef long long LL; 
typedef long double LD;
typedef pair<int,int> pii;
typedef pair<LL, LL> pll;

const int MAX = 1e5 + 5;

LL dp[MAX];

int q;

vector<int> lena_sort(vector<int> nums) {
	if (nums.size() <= 1) {
		return nums;
	}
	int pivot = nums[0];
	vector<int> less;
	vector<int> more;
	for (int i = 1; i < nums.size(); ++i) {
		// Comparison
		q += 1;
		if (nums[i] < pivot) {
			less.push_back(nums[i]);
		}
		else {
			more.push_back(nums[i]);
		}
	}
	vector<int> sorted_less = lena_sort(less);
	vector<int> sorted_more = lena_sort(more);
	vector<int> ans;
	for(auto it : sorted_less) ans.push_back(it);
	ans.push_back(pivot);
	for(auto it : sorted_more) ans.push_back(it);
	// ans = sorted_less + pivot + sorted_more;   
	return ans;
}

int main() {
	#ifndef ONLINE_JUDGE
		//freopen("inp.txt", "r", stdin);
	#endif
	dp[1] = 0;
	dp[2] = 1;
	for(int i = 3; i < MAX; ++i) {
		dp[i] = i-1 + dp[i/2] + dp[(i-1)/2];
	}
	int t;
	LL n, c;
	scanf("%d", &t);
	while(t--) {
		scanf("%lld %lld", &n, &c);
		if (n == 1) {
			if (c == 0) {
				printf("1\n");
			}
			else {
				printf("-1\n");
			}
			continue;
		}
		LL w = n * (n-1) / 2;
		if (w < c) {
			printf("-1\n");
			continue;
		}
		else if (c < dp[n]) {
			printf("-1\n");
			continue;
		}
		assert(dp[n] <= c && c <= w);
		vector<int> a(n);
		for(int i = 1; i <= n; ++i) {
			a[i-1] = i;
		}
		do {
			q = 0;
			vector<int> ans = lena_sort(a);
			if (q == c) {
				for(auto it : a) printf("%d ", it);
				break;
			}
		}while(next_permutation(a.begin(), a.end()));
		printf("\n");
	}
	return 0;
}