using System;
using System.Text;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
using static System.Console;
using static System.Math;

namespace AtCoder
{
    public class Program
    {
        public static void Main(string[] args)
        {
            new Program().Solve(new ConsoleInput(Console.In, ' '));

            return;
        }

        public void Solve(ConsoleInput cin)
        {

            var N = cin.ReadInt;
            int[] A = new int[N + 1];
            for (int i = 1; i < N + 1; i++)
            {
                A[i] = cin.ReadInt;
            }

            int[] L = new int[N + 2];
            int[] R = new int[N + 2];

            L[0] = 0;
            R[N + 1] = 0;

            for (int i = 1; i < N + 1; i++)
            {
                L[i] = Gcd(L[i - 1], A[i]);
            }
            for (int i = N; i > 0; i--)
            {
                R[i] = Gcd(R[i + 1], A[i]);
            }

            int[] M = new int[N + 1];
            for (int i = 1; i < N + 1; i++)
            {
                M[i] = Gcd(L[i - 1], R[i + 1]);
            }
            Console.WriteLine(M.Max());

        }
        public int Gcd(int a, int b)
        {
            if(a == 0) return b;
            if(b == 0) return a;
            if (a < b) {
                return Gcd(b, a);
            }
            while (b != 0) {
                int remainder = a % b;
                a = b;
                b = remainder;
            }
            return a;
        }

    }

    public static class Extensions
    {
        public static string Reverse(this string sourse)
        {
            char[] chrAry = sourse.ToCharArray();
            Array.Reverse(chrAry);
            return new string(chrAry);
        }
    }

    public class ConsoleInput
    {
        private readonly System.IO.TextReader _stream;
        private char _separator = ' ';
        private Queue<string> inputStream;
        public ConsoleInput(System.IO.TextReader stream, char separator = ' ')
        {
            this._separator = separator;
            this._stream = stream;
            inputStream = new Queue<string>();
        }
        public string Read
        {
            get
            {
                if (inputStream.Count != 0) return inputStream.Dequeue();
                string[] tmp = _stream.ReadLine().Split(_separator);
                for (int i = 0; i < tmp.Length; ++i)
                    inputStream.Enqueue(tmp[i]);
                return inputStream.Dequeue();
            }
        }
        public string ReadLine { get { return _stream.ReadLine(); } }
        public int ReadInt { get { return int.Parse(Read); } }
        public long ReadLong { get { return long.Parse(Read); } }
        public double ReadDouble { get { return double.Parse(Read); } }
        public string[] ReadStrArray(long N) { var ret = new string[N]; for (long i = 0; i < N; ++i) ret[i] = Read; return ret; }
        public int[] ReadIntArray(long N) { var ret = new int[N]; for (long i = 0; i < N; ++i) ret[i] = ReadInt; return ret; }
        public long[] ReadLongArray(long N) { var ret = new long[N]; for (long i = 0; i < N; ++i) ret[i] = ReadLong; return ret; }
    }
}


Measured memory_bytes: 26844