#include <bits/stdc++.h>
using namespace std;

int main(){
  int N;
  vector<int> A;
  
  cin>>N;
  for(int i=0;i<N;i++){
    int x;
    cin>>x;
    A.push_back(x);
  }
  
  sort(A.begin(),A.end());
  int M = A.at(1);
  
  int answer;
  
  for(int i=M;i>0;i--){
    int x=0;
    for(int j=0;j<N;j++){
      if (A.at(j)%i!=0) x++;
      if (x>1) break;
    }
    if (x<=1) {
      answer = i;
      break;
    }
  }
  
  cout<<answer<<endl;
}