#include <iostream>
#include<vector>
#include<algorithm>
#include<math.h>
#include<stdio.h>
#include<set>
#include<map>
#include<array>
#include<unordered_map>
#include<unordered_set>
using namespace std;
#define mod 1000000007
#define test int t;scanf("%d", &t);while(t--)
#define pb push_back
#define all(x) x.begin(),x.end() 
#define mpr make_pair
#define ll long long int 
#define ull unsigned long long int 
#define db double
#define vi vector<int>
#define vii vector<pair<int,int> >
#define pii pair<int,int>
#define vl vector<ll>
#define vll vector<pair<ll,ll> >
#define pll pair<ll,ll>
#define ub upper_bound
#define lb lower_bound
 
#define sc(x) scanf("%d",&x)
#define sc2(x,y) scanf("%d%d",&x,&y)    
#define sc3(x,y,z) scanf("%d%d%d",&x,&y,&z)
#define sc4(w,x,y,z) scanf("%d%d%d%d",&w,&x,&y,&z)
 
#define scll(x) scanf("%lld",&x)
#define scll2(x,y) scanf("%lld%lld",&x,&y)
#define scll3(x,y,z) scanf("%lld%lld%lld",&x,&y,&z)
#define scll4(w,x,y,z) scanf("%lld%lld%lld%lld",&w,&x,&y,&z)
 
#define scdb(x) scanf("%lf",&x)
#define scdb2(x,y) scanf("%lf%lf",&x,&y)    
#define scdb3(x,y,z) scanf("%lf%lf%lf",&x,&y,&z)
#define scdb4(w,x,y,z) scanf("%lf%lf%lf%lf",&w,&x,&y,&z)
 
#define scs(s) scanf("%s", s)
 
#define pr(x) printf("%d\n",x)
#define pr2(x,y) printf("%d %d\n",x,y)
#define pr3(x,y,z) printf("%d %d %d\n",x,y,z)
#define pr4(w,x,y,z) printf("%d %d %d %d\n",w,x,y,z)
 
#define prll(x) printf("%lld\n",x)
#define prll2(x,y) printf("%lld %lld\n",x,y)
#define prll3(x,y,z) printf("%lld %lld %lld\n",x,y,z)
#define prll4(w,x,y,z) printf("%lld %lld %lld %lld\n",w,x,y,z)
 
#define prdb(x) printf("%lf\n",x)
#define prdb2(x,y) printf("%lf %lf\n",x,y)
#define prdb3(x,y,z) printf("%lf %lf %lf\n",x,y,z)
#define prdb4(w,x,y,z) printf("%lf %lf %lf %lf\n",w,x,y,z)
 
#define prs(s) printf("%s\n", s)
#define prn() printf("\n")
#define prvec(v) for(int i=0;i<v.size();i++) cout << v[i] << " "
#define prpair(p) cout<<p.first<<" "<<p.second<<endl
#define F first
#define S second
 
#define maxr 100005
pair<ll,ll> m[maxr];
vector<pair<int,int> > ans;
int pos;
vector<int> vis(maxr,0);
void rec(int len, int c, int pos, int l, int r)
{
  //cout<<len<<" "<<c<<" "<<pos<<endl;
  if(len==0)return;
  if(len==1)
  {
    for(int j=l;j<=r;j++)
      if(!vis[j])
      {
        vis[j] = 1;
        ans.pb(mpr(pos,j));
        break;
      }
    return;
  }
  c-=(len-1);
  for(int i=0;i<len;i++)
  {
    ll mi = m[i].F+m[len-1-i].F;
    ll ma = m[i].S+m[len-1-i].S;
    if(c>=mi && c<=ma)
    {
      int cnt = 0, j;
      for(j=l;j<=r;j++)
      {
        if(vis[j])continue;
        if(cnt==i)break;
        cnt++;
      }
      vis[j] = 1;
      ans.pb(mpr(pos,j));
      ll dif = c-mi, c1 = m[i].F, c2 = m[len-1-i].F;
      if(c1+dif>m[i].S)
      {
        c1 = m[i].S;
        c2 = c-c1;
      }
      else c1 += dif;
      rec(i,c1,pos+1,l,j-1);
      rec(len-1-i,c2,pos+1+i,j+1,r);
      break;
    }
  }
}
int main()
{
  m[0] = mpr(0,0);
  m[1] = mpr(0,0);
  for(int i=2;i<maxr;i++)
    m[i] = mpr(i-1+m[i/2].F+m[(i-1)/2].F,i-1+m[i-1].S);
  //for(int i=0;i<=5;i++)prpair(m[i]);
  test
  {
    pos = 1;
    ans.clear();
    int len, c;
    cin>>len>>c;
    if(c<m[len].F || c>m[len].S)cout<<-1<<endl;
    else
    {
      rec(len,c,0,1,len);
      sort(all(ans));
      for(int i=0;i<ans.size();i++)cout<<ans[i].S<<" ";
      prn();
    }
    for(int i=0;i<=len;i++)vis[i] = 0;
  }
  return 0;
}