#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <stack>
#include <queue>
#include <functional>
#include <math.h>
#include <stdlib.h>
#include <map>
#include <deque>
#include <list>
#include <sys/timeb.h>
#include <fstream>
#include <set>

using namespace std;

#define repr(i,a,b) for(int i=(int)(a);i<(int)(b);i++)
#define rep(i,n) repr(i,0,n)
#define reprrev(i,a,b) for(int i=(int)(b)-1;i>=(int)(a);i--)
#define reprev(i,n) reprrev(i,0,n)
#define repi(itr,ds) for(auto itr=ds.begin();itr!=ds.end();itr++)
#define all(a) (a).begin(),(a).end()
#define rall(a) (a).rbegin(),(a).rend()
#define mp make_pair
#define mt make_tuple
#define INF 1050000000
#define INFL 1100000000000000000LL
#define EPS (1e-10)
#define MOD 1000000007
#define PI 3.1415926536
#define RMAX 4294967295

typedef long long ll;
typedef pair<int, int> Pi;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<bool> vb;
typedef vector<char> vc;
typedef vector<string> vs;
typedef vector<double> vd;
typedef vector<Pi> vPi;
typedef vector<vector<int> > vvi;
typedef vector<vector<bool> > vvb;
typedef vector<vector<ll> > vvll;
typedef vector<vector<char> > vvc;
typedef vector<vector<string> > vvs;
typedef vector<vector<double> > vvd;
typedef vector<vector<Pi> > vvPi;
typedef priority_queue<int, vector<int>, greater<int> > pqli;
typedef priority_queue<ll, vector<ll>, greater<ll> > pqlll;
typedef priority_queue<Pi, vector<Pi>, greater<Pi> > pqlP;
struct Edge {
	int from, to, cost;
	bool operator<(Edge e) {
		return cost < e.cost;
	}
};
typedef vector<Edge> Edges;
typedef vector<Edges> Graph;
template <class T>
using vec = vector<T>;
template<class T>
using pql = priority_queue<T, vector<T>, greater<T>>;
string debug_show(Pi a) {
	return "(" + to_string(a.first) + "," + to_string(a.second) + ")";
}

template<class T>
struct augEdge {
	T from, to;
	int cost;
	bool operator<(augEdge e) { return cost < e.cost; }
	bool operator>(augEdge e) { return cost > e.cost; }
};
template<class T>
using augGraph = vector<augEdge<T>>;


bool pairCompare(const Pi& firstElof, const Pi& secondElof)
{
	return firstElof.second > secondElof.second;
}

ll gcd(ll a, ll b) {
	ll temp;
	while (a % b != 0)
	{
		temp = b;
		b = a % b;
		a = temp;
	}
	return b;
}

ll lcm(ll a, ll b) {
	return a / gcd(a, b) * b;
}

int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);

	int n;
	cin >> n;
	vll a(n);
	ll maxa = 0;
	rep(i, n) {
		cin >> a[i];
		maxa = max(maxa, a[i]);
	}
	ll ans = 0;
	vll beforegcd(n);
	vll aftergcd(n);
	beforegcd[0] = a[0];
	aftergcd[n - 1] = a[n - 1];
	repr(i, 1, n) {
		beforegcd[i] = gcd(a[i], beforegcd[i - 1]);
	}
	for (int i = n - 2; i >= 0; i--) {
		aftergcd[i] = gcd(aftergcd[i + 1], a[i]);
	}

	rep(i, n) {
		//cout << beforegcd[i] << " " << aftergcd[i] << endl;
	}
	rep(i, n) {
		if (i == 0) {
			// cout <<beforegcd[n - 1 - 1] << endl;;
			ans = max(ans, aftergcd[1]);
		}
		else if (i == n - 1) {
			// cout << aftergcd[1] << endl;
			ans = max(ans, beforegcd[n - 2]);
		}
		else {
			// cout << beforegcd[i - 1] << " " << aftergcd[n - 1-i] << endl;
			ans = max(ans, gcd(beforegcd[i - 1], aftergcd[i+1]));
		}
		//cout << beforegcd[i] << " " << aftergcd[i] << endl;

	}
	cout << ans << endl;
	return 0;
}



Measured memory_bytes: 2560