using System;
using System.Collections.Generic;
using System.Linq;
using static System.Console;
using static System.Convert;
using static System.Math;
//using Debug;
//using static System.Globalization.CultureInfo;
using System.Text;
class Program
{
    static void Main(string[] args)
    {
        Solve();
        //WriteLine(Solve());
    }
    static void Solve()
    {
        var num = Input.num;
        var ar = Input.ar;
        Func<int, int, int> func = (int a, int b) => Calculation.GCD(a, b);
        var seg = new SegmentTree<int>(num + 2, 0, func);
        for (var i = 1; i <= num; i++)
            seg.Update(i, ar[i-1]);
        var res = 1;
        for (var i = 1; i <= num; i++)
            res = Max(res, func(seg.query(0, i), seg.query(i + 1, num + 2)));
        WriteLine(res);
    }
}

public class Input
{
    public static string read => ReadLine();
    public  static int[] ar => Array.ConvertAll(read.Split(' '), int.Parse);
    public  static int num => ToInt32(read);
    public static long[] arL => Array.ConvertAll(read.Split(' '), long.Parse);
    public  static long numL => ToInt64(read);
    public static char[][] gred(int h) 
        => Enumerable.Repeat(0, h).Select(v => read.ToCharArray()).ToArray();
    public static int[][] ar2D(int num)
        => Enumerable.Repeat(0, num).Select(v => ar).ToArray();
    public static long[][] arL2D(int num)
        => Enumerable.Repeat(0, num).Select(v => arL).ToArray();
    public static T getValue<T>(string g)
    {
        var t = typeof(T);
        if (t == typeof(string))
            return (T)(object)g;
        if (t == typeof(int))
            return (T)(object)int.Parse(g);
        if (t == typeof(bool))
            return (T)(object)bool.Parse(g);
        if (t == typeof(long))
            return (T)(object)long.Parse(g);
        return default(T);
    }
    public const long Inf = (long)1e18;
    public const double eps = 1e-6;
    public  const string Alfa = "abcdefghijklmnopqrstuvwxyz";
    public  const int MOD = 1000000007;
}

public class Calculation
{
    public static int LCM(int num1, int num2)
    {
        return num1 / GCD(num1, num2) * num2;
    }

    public static long LCM(long num1, long num2)
    {
        return num1 / GCD(num1, num2) * num2;
    }

    public static int GCD(int num1, int num2)
    {
        return num1 < num2 ? GCD(num2, num1) :
            num2 > 0 ? GCD(num2, num1 % num2) : num1;
    }

    public static long GCD(long num1, long num2)
    {
        return num1 < num2 ? GCD(num2, num1) :
            num2 > 0 ? GCD(num2, num1 % num2) : num1;
    }

    public static List<int> PrimeList(long num)
    {
        if (num < 2) return new List<int>();
        var prime = new List<int> { 2 };
        var bo = new bool[num + 1];
        for (var i = 3; i <= num; i += 2)
            if (!bo[i])
            {
                prime.Add(i);
                for (var j = 3 * i; j <= num; j += 2 * i)
                    bo[j] = true;
            }
        return prime;
    }

    public static Dictionary<long,int> Factorize(long num)
    {
        var dic = new Dictionary<long, int>();
        for(var i = 2; i * i <= num; i++)
        {
            var ct = 0;
            while (num % i == 0)
            {
                ct++;
                num /= i;
            }
            if (ct != 0) dic[i] = ct;
        }
        if (num != 1) dic[num] = 1;
        return dic;
    }
}

public class SegmentTree<T>
{
    private List<T> item;
    private int _num;
    private Func<T, T, T> _func;
    private Func<T, T, T> updateFunc;
    private T _init;

    private int Parent(int index)
        => (index + 1) / 2 - 1;
    private int Left(int index)
        => 2 * index + 1;
    private int Right(int index)
        => 2 * (index + 1);

    public SegmentTree(int num, T init, Func<T, T, T> func, Func<T, T, T> updateFunc = null)
    {
        _func = func;
        _num = 1;
        _init = init;
        this.updateFunc = updateFunc ?? ((T val1, T val2) => val2);
        while (_num < num)
            _num *= 2;
        item = new List<T>(2 * _num - 1);
        for (var i = 0; i < 2 * _num - 1; i++)
            item.Add(init);
    }
    public void Update(int index, T value)
    {
        index += _num - 1;
        item[index] = updateFunc(item[index], value);
        while (Parent(index) >= 0)
        {
            index = Parent(index);
            item[index] = _func(item[Left(index)], item[Right(index)]);
        }
    }
    public T query(int left, int right)
        => query(left, right, 0, 0, _num);
    private T query(int left, int right, int k, int l, int r)
    {
        if (r <= left || right <= l) return _init;
        if (left <= l && r <= right) return item[k];
        else
            return _func(query(left, right, Left(k), l, (l + r) / 2), query(left, right, Right(k), (l + r) / 2, r));
    }
}


Measured memory_bytes: 26204