#include <bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define pi M_PI
#define R cin>>
#define Z class
#define ll long long
#define ln cout<<'\n'
#define in(a) insert(a)
#define pb(a) push_back(a)
#define pd(a) printf("%.10f\n",a)
#define mem(a) memset(a,0,sizeof(a))
#define all(c) (c).begin(),(c).end()
#define iter(c) __typeof((c).begin())
#define rrep(i,n) for(int i=(int)(n)-1;i>=0;i--)
#define REP(i,m,n) for(int i=(int)(m);i<(int)(n);i++)
#define rep(i,n) REP(i,0,n)
#define tr(it,c) for(iter(c) it=(c).begin();it!=(c).end();it++)
template<Z A>void pr(A a){cout<<a;ln;}
template<Z A,Z B>void pr(A a,B b){cout<<a<<' ';pr(b);}
template<Z A,Z B,Z C>void pr(A a,B b,C c){cout<<a<<' ';pr(b,c);}
template<Z A,Z B,Z C,Z D>void pr(A a,B b,C c,D d){cout<<a<<' ';pr(b,c,d);}
template<Z A>void PR(A a,ll n){rep(i,n){if(i)cout<<' ';cout<<a[i];}ln;}
ll check(ll n,ll m,ll x,ll y){return x>=0&&x<n&&y>=0&&y<m;}
const ll MAX=1000000007,MAXL=1LL<<61,dx[4]={-1,0,1,0},dy[4]={0,1,0,-1};
typedef pair<int,int> P;

ll c,n,m;
vector<ll> dfs(int l,int r) {
  vector<ll> v;
  for(int i=l; i<=r; i++) v.pb(i);
  if(v.size()<=1) return v;
  rrep(i,(v.size()+1)/2) {
    ll x=i*(v.size()-i-1);
    if(c-x>=m) {
      c-=x;
      vector<ll> a=dfs(l,v[i]-1),b=dfs(v[i]+1,r);
      ll z=v[i];
      v.clear();
      v.pb(z);
      rep(j,a.size()) v.pb(a[j]);
      rep(j,b.size()) v.pb(b[j]);
      break;
    }
  }
  return v;
}

void Main() {
  ll T;
  R T;
  while(T--) {
    cin >> n >> m;
    if((n-1)*n/2<m) {
      pr(-1);
      continue;
    }
    c=(n-1)*n/2;
    vector<ll> a=dfs(1,n);
    if(c!=m) pr(-1);
    else PR(a,n);
  }
}

int main(){ios::sync_with_stdio(0);cin.tie(0);Main();return 0;}