using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
class Solution {

    static long maximumValue(int[] a) {
        
        int fMax = int.MinValue;
        
        for(int i = 0; i < a.Length; ++i)
        {
            for(int j = i; j < a.Length; ++j)
            {
                var subArray = a.Skip(i).Take(j - i + 1).ToArray();
                
                int gcd = Gcd(Math.Abs(a[i]), Math.Abs(a[j]));
                int sum = subArray.Sum();
                int max = subArray.Max();
                           
                //Console.WriteLine($"{a[i]} {a[j]} => {gcd} {sum} {max}");
                
                int f = gcd * (sum - max);
                if(f > fMax)
                {
                    fMax = f;
                }
            }
        }
        
        return fMax;
    }

    static int Gcd(int a, int b)
    {
        return b == 0 ? a : Gcd(b, a % b);
    }
    
    static void Main(String[] args) {
        int n = Convert.ToInt32(Console.ReadLine());
        string[] a_temp = Console.ReadLine().Split(' ');
        int[] a = Array.ConvertAll(a_temp,Int32.Parse);
        long result = maximumValue(a);
        Console.WriteLine(result);
    }
}