#include<bits/stdc++.h>
using namespace std;
const int INF = INT_MAX;
#define ll long long
#define tie ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define w(t) int t;cin>>t;while(t--)
#define inf 1e18
#define l length()
void solve(){
}
int main(){
    tie
    w(t){
        int n,k;
        cin>>n>>k;
        if((n<3 && k!=0) || n<=k || (n-1)/2<k) {cout<<"-1\n";continue;}
        if(k==0){
            for(int i=1;i<=n;i++) cout<<i<<" ";
            cout<<"\n";
            continue;
        }
        int i=1;
        cout<<i<<" "<<i+2<<" "<<i+1<<" ";
        i=4;n-=3;
        k--;
        while(k!=0){
            cout<<i+1<<" "<<i<<" ";
            k--;i+=2;n-=2;
        }
        while(n!=0) { cout<<i<<" ";i++;n--;}
        cout<<"\n";
    }
}