#include <bits/stdc++.h>
using namespace std;
#define sint(x) scanf("%d", &x)
#define slld(x) scanf("%lld", &x)
#define sstr(x)	scanf("%s", x)
#define slf(x)	scanf("%lf", &x)
#define sLf(x)	scanf("%Lf", &x)
#define pint(x) printf("%d", x)
#define plld(x) printf("%lld", x)
#define pstr(x)	printf("%s", x)
#define plf(x)	printf("%lf", x)
#define pLf(x)	printf("%Lf", x)
#define nl putchar('\n')
#define spc printf(" ")
#define MAX2 108
#define MAX3 1008
#define MAX4 10008
#define MAX5 100008
#define MAX6 1000008
#define MAX7 10000008
#define MOD 1000000007
#define ll long long
#define lf double
#define Lf long double

#define PB push_back

#define MEM(a, b) memset(a, (b), sizeof(a))
#define CLR(a) memset(a, 0, sizeof(a))
#define ABS(X) ( (X) > 0 ? (X) : ( -(X) ) )
#define S(X) ( (X) * (X) )
#define SZ(V) (int )V.size()
#define FORN(i, n) for(i = 0; i < n; i++)
#define FORABD(i, a, b) for(i = a; i >= b; i--)
#define FORAB(i, a, b) for(i = a; i <= b; i++)
#define REP(i ,n) FORAB(i, 0, n)
#define ALL(V) V.begin(), V.end()
#define IN(A, B, C)  (B) <= (A) && (A) <= (C)

typedef pair<int,int> PII;
typedef pair<double, double> PDD;
typedef vector<int> VI;
typedef vector< VI >	VVI;

#define AIN(A, B, C) assert(IN(A, B, C))

//typedef int LL;
//typedef long long int LL;
//typedef __int64 LL;

#define boost	ios_base::sync_with_stdio(false);	cin.tie(NULL);	cout.tie(NULL)
#define all(x)	x.begin(), x.end()
#define	sz(x)	int( (x).size() )
#define eb	emplace_back
#define	pb	push_back
#define	mp	make_pair
#define ft	first
#define sd	second
#define DFORAB(i, a, b)	for(i = a; i >= b; i--)

int main() {
	int t, n, i, j, k, l, r, m, p, q;

	sint(t);
	while(t--) {
		int len, c;
		sint(len); sint(c);

		int a[len+1];
		bool b[len+1];
		int status = 0;
		CLR(b);
			if(c < len * len) {
				status = 1;
			}
//pint(status); nl;
		k = len-1;

		if(status == 1) {

			int idx = 1;
			while(k > 0 && c > 0) {
				a[idx] = k;
pint(k); spc;
				b[k] = true;
				idx++;

				c -= k;
				if(k >= c) {
					k = c;
				}
				else	k--;

//pint(k); nl;
			}

			FORAB(i, 1, len) {
				if(b[i] == false) {
pint(i); spc;
//					a[idx] == i;
//					idx++;	
				}
			}

//			FORAB(i, 1, len) {
//				pint(a[i]);
//				spc;
//			}
		}
		else pint(-1);
		nl;
	}
	return 0;
}