#include <bits/stdc++.h>
#define int long long

#define MULTITEST true

using namespace std;
vector<vector<int> >g;
vector<vector<int>>conn;
vector<int>siz,used,used1;
bool try_kuhn(int x){
   // cout<<x<<' '<<used[x]<<endl;
    if(used[x]){
        return false;
    }
    //cout<<x<<endl;
    used[x]=1;
    //cout<<g.size()<<' '<<endl;
    for(int i=0;i<g[x].size();i++){
        //cout<<i<<endl;
        int to = g[x][i];
        //cout<<to<<endl;
        if(siz[to]){
            conn[to].push_back(x);
            siz[to]--;
            return true;
        }
        for(int j=0;j<conn[to].size();j++){
            if(try_kuhn(conn[to][j])){
                conn[to][j]=x;
                return true;
            }
        }
    }
    return false;

}
void solve () {
    g.clear();
    conn.clear();
    siz.clear();
    int n;
    cin>>n;
    map<int,int>a;
    for(int i=0;i<n;i++){
        int x;
        cin>>x;
        a[x]++;
    }
    vector<pair<int,int> >b;
    for(auto i:a){
        b.push_back(i);
    }
    used1.clear();
    used1.resize(b.size());
    conn.resize(b.size());
    for(int i=0;i<b.size();i++){
        siz.push_back(b[i].second);
    }
    priority_queue<int> timer;
    for(auto i:b){
        timer.push({-i.first});
    }
    int ans = 0;
    while(true){
        int x = timer.top();
        timer.pop();
        vector<int>timerok;
        while(!timer.empty()&&timer.top()==x){
            timer.pop();
        }

        g.resize(g.size()+1);
        for(int i=0;i<b.size();i++){
            //cout<<x<<' '<<b[i].first<<' '<<g.size()<<' '<<b.size()<<endl;
            if(x % b[i].first == 0){
                g[g.size()-1].push_back(i);
            }
        }
        used.resize(g.size());
        used.assign(g.size(),0);
        //cout<<42<<endl;
        bool ok = try_kuhn(g.size()-1);
        if(ok){
            for(auto i:g[g.size()-1]){
                if(!used1[i])
                timer.push(-b[i].first+x);
            }
        }
        else{
            for(auto i:g[g.size()-1]){
                used1[i]=1;
            }
        }
        ans+=ok;
        if(ans==n){
            cout<<-x<<'\n';
            break;
        }

    }


}

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.precision(30);
    
    int T = 1;
    if (MULTITEST) cin >> T;

    for (int t = 0; t < T; t ++)
        solve();
}