/**
* Created by LXF on 2017/8/10.
*/
import java.util.Scanner;
public class Main {
/** 请完成下面这个函数，实现题目要求的功能 **/
/** 当然，你也可以不按照这个模板来作答，完全按照自己的想法来 ^-^ **/
// static int maxScore(int[] score) {
// int[] max = new int[score.length];
// for(int i=0;i) {
// int left = 1;
// }
// }
// }
//
// }
static int maxScore(int[] score) {
int n = score.length;
int[] nums = new int[n + 2];
for (int i = 0; i < n; i++)
nums[i + 1] = score[i];
nums[0] = nums[n + 1] = 1;
int[][] alibaba = new int[n + 2][n + 2];
for (int k = 1; k <= n; k++) {
for (int i = 1; i <= n - k + 1; i++) {
int j = i + k - 1;
for (int x = i; x <= j; x++) {
alibaba[i][j] = Math.max(alibaba[i][j], alibaba[i][x - 1] + nums[i - 1] * nums[x] * nums[j + 1] + alibaba[x + 1][j]) ;
}
}
}
return alibaba[1][n];
}
public static void main(String[] args){
Scanner in = new Scanner(System.in);
int res;
int _score_size = 0;
_score_size = Integer.parseInt(in.nextLine().trim());
int[] _score = new int[_score_size];
int _score_item;
for(int _score_i = 0; _score_i < _score_size; _score_i++) {
_score_item = Integer.parseInt(in.nextLine().trim());
_score[_score_i] = _score_item;
}
res = maxScore(_score);
System.out.println(String.valueOf(res));
}
}