#include <bits/stdc++.h>
#define NN 505
using namespace std;
ifstream fin ("podm.in");
ofstream fout ("podm.out");

int n;
int d[NN];
long long dp[NN][NN], sm, sc;

int main()
{
    fin >> n;
    for(int i = 1 ; i <= n + 1 ; i++)
        fin >> d[i];
    for(int i = 1, j = 2 ; j <= n ; i++, j++)
    {
        dp[i][j] = d[i] * d[j] * d[j+1];
    }
    for(int di = 3 ; di <= n ; di++)
    {
        for(int i = 1, j = di ; j <= n ; i++, j++)
        {
            sm = dp[i+1][j] + d[i] * d[i+1] * d[j+1];
            for(int k = i + 1 ; k < j ; k++)
            {
                sc = dp[i][k] + dp[k+1][j] + d[i] * d[k+1] * d[j+1];
                sm = min(sc, sm);
            }
            dp[i][j] = sm;
        }
    }
    fout << dp[1][n];
    return 0;
}