#include <iostream>
#include <fstream>
using namespace std;
ifstream f ("a.in");
ofstream g ("a.out");
int n;
int dim[501],dp[501][501];
int main()
{
    f >> n;
    for(int i = 1;i<=n+1;i++)
        f >> dim[i];
    int dif = 1,i,j;
    while(dif!=n-1)
    {
        i = 1;
        j = i+dif;
        for(int k = i;k<=j-1;k++)
        {
            if(dp[i][j]==0)
            {
                dp[i][j] = dp[i][k] + dp[k+1][j] + (dim[k]*dim[i]*dim[j]);
            }
            else
            {
                dp[i][j] = min(dp[i][j],dp[i][k] + dp[k+1][j] + (dim[k]*dim[i]*dim[j]));
            }
        }
    }
    g<<dp[1][n];
}