#include <bits/stdc++.h>

using namespace std;

ifstream in ("podm.in");
ofstream out ("podm.out");

#define int long long

const int dim = 505;

int dp[dim][dim];
int a[dim];

signed main()
{
    int n;
    in >> n;

    for (int i=1; i<=n+1; i++)
        in >> a[i];

    for (int i=1; i<=n; i++)
        for (int j=1; j<=n; j++)
            dp[i][j] = 2e18;

    for (int i=1; i<=n; i++)
    {
        dp[i][i] = 0;
        if (i != n)
            dp[i][i+1] = a[i] * a[i+1] * a[i+2];
    }

    for (int d=2; d<=n; d++)
    {
        for (int i=1; i+d<=n; i++)
        {
            for (int j=i; j<i+d; j++)
                dp[i][i+d] = min(dp[i][i+d], dp[i][j] + dp[j+1][i+d] + a[i] * a[i+d+1] * a[j+1]);
        }
    }

    out << dp[1][n];

    return 0;
}