//#pragma GCC optimize("unroll-loops")
//#pragma GCC optimize ("Ofast")
//#pragma comment(linker, "/stack:200000000000")

#include <iostream>
#include <ctime>
#include <iomanip>
#include <vector>
#include <map>
#include <algorithm>
#include <cmath>
#include <set>
#include <stack>
#include <cassert>
#include <queue>
#include <deque>

using namespace std;

//#define int long long

vector<int> factors(1e6+7);

void fct(int n){
    int i;
    for(i=1;i*i<=n;i++){
        if(n%i==0){
            factors[i]++;
            factors[n/i]++;
        }
    }
    int tmp=sqrt(n);
    if(tmp*tmp==n) factors[tmp]--;
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    int n;
    cin >> n;
    for(int i=0;i<n;i++){
        int x;
        cin >> x;
        fct(x);
    }
    for(int i=1e6+6;i>0;i--){
        if(factors[i]>1){
            cout << i << endl;
            return 0;
        }
    }
}