#include <bits/stdc++.h>
#define r(i,n) for(int i = 0; i<n; i++)
using namespace std;

int gcd(int a, int b){
  if(b==0)return a;
  else return gcd(b,a%b);
}

int main() {
  int n,ans=1;
  cin >> n;
  vector<int> v(n),l(n,0),q(n,0);
  r(i,n)cin>>v[i];
  r(i,n-1)l[i+1]=gcd(l[i],v[i]);
  r(i,n-1)q[n-i-2]=gcd(q[n-i-1],v[n-i-1]);
  r(i,n)ans=max(ans,gcd(l[i],q[i]));
  cout << ans << endl;
}
