import java.io.*;

public class Main {

    static BufferedReader read = new BufferedReader(new InputStreamReader(System.in));
    static int N = 210;
    static int[] a = new int[N];
    static long[][] dp = new long[N][N];
    public static void main(String[] args) throws Exception{
        int n = Integer.valueOf(read.readLine());
        String[] ss = read.readLine().split(" ");
        for(int i = 0; i < n; i++){
            a[i] = Integer.valueOf(ss[i]);
            a[i + n] = Integer.valueOf(ss[i]);
        }

        for(int len = 3; len <= n + 1; len ++){
            for(int i = 0; i + len - 1 < 2 * n; i++){          //注意 这里i的边界
                int j = i + len - 1;
                for(int k = i + 1; k < j; k++){
                    dp[i][j] = Math.max(dp[i][k] + dp[k][j] + a[i] * a[k] * a[j], dp[i][j]);  
                }
            }
        }
        long max = 0;
        for(int i = 0; i < n; i++){
            max = Math.max(dp[i][i + n], max);
        }
        System.out.println(max);
    }
}