#include <fstream>
#include <climits>
using namespace std;

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

const int NMAX = 501;
int n;
long long dp[NMAX][NMAX];
struct mat
{
    long long cols, rows;
} mats[NMAX];

int main()
{
    cin >> n;
    long long last;
    cin >> last;
    long long current;
    for (int i = 1; i <= n; i++) {
        cin >> current;
        mats[i].rows = last;
        mats[i].cols = current;
        last = current;
    }

    for (int lg = 1; lg <= n; lg++) {
        for (int i = 1; i <= n - lg + 1; i++) {
            int j = i + lg - 1;
            if (lg == 1) {
                dp[i][j] = 0;
            } else if (lg == 2) {
                dp[i][j] = mats[i].rows * mats[i].cols * mats[j].cols;
            } else {
                dp[i][j] = LLONG_MAX;
                for (int k = i; k < j; k++) {
                    dp[i][j] = min(dp[i][k] + dp[k + 1][j] + mats[i].rows * mats[k].cols * mats[j].cols, dp[i][j]);
                }
            }
        }
    }
    cout << dp[1][n];
    return 0;
}