#include <iostream>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <cstdlib>
#include <cmath>
#include <cstring>
#include <iomanip>
using namespace std;

const int N = 2e5 + 5, inf = 1e9;
#define pb push_back
#define mp make_pair
#define ll long long
#define ff first
#define ss second
#define all(a) a.begin(),a.end()
#define sz(x) (int)x.size()
typedef vector<int> vi;
typedef pair<int,int> ii;
typedef vector<ii> vii;

void solve(){
    int l, r;
    cin >> l >> r;
    int idx = -1;
    for(int i = l; i < r; i++){
        if(__gcd(r, i) == 1){
            idx = i;
            break;
        }

    }

    if(idx == -1 || idx != l){
        cout << "-1\n";
        return;
    }
    for(int i = l; i <= r; i++){
        if(i != r)cout << i + 1 << ' ';
        else cout << idx << ' ';
    }
    cout << '\n';
}

int main(){
    ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
    int t = 1;
    cin >> t;
    while(t--){
        solve();
    }
    return 0;
}