N = int(input())
arr = list( map(int, input().split()) )

from functools import lru_cache
# 序号i到j的节点序列的所有划分方案里面权值乘积之和的最小数值
@lru_cache(typed=False, maxsize=128000000)
def dp(i, j):

    if j == i+2:
        return arr[i]*arr[i+1]*arr[i+2]
    else:
        # i-j连起来的这条边不动，枚举根这条边配对的点的位置，枚举切割位置
        ans = 0x7ffffffffffffffffffffffffffff
        for k in range(i+1, j):
            if k == i+1:
                ans = min(ans, arr[i]*arr[k]*arr[j] + dp(k, j))
            elif k == j-1:
                ans = min(ans, arr[i]*arr[k]*arr[j] + dp(i, k))
            else:
                ans = min(ans, arr[i]*arr[k]*arr[j] + dp(i, k) + dp(k, j))
        return ans

print(dp(0, N-1))