#include <iostream>
#include <fstream>
#include <limits>

using namespace std;

const int MAXN = 511;

long long matrix_chain_cost(int n, short d[]) {
    long long m[MAXN][MAXN];
    for (int i = 1; i <= n; i++) {
        m[i][i] = 0;
        m[i][i + 1] = d[i - 1] * d[i] * d[i + 1];
    }

    for (int l = 3; l <= n; l++) {
        for (int i = 1; i <= n - l + 1; i++) {
            int j = i + l - 1;
            m[i][j] = numeric_limits<long long>::max();
            for (int k = i; k <= j - 1; k++) {
                long long q = m[i][k] + m[k + 1][j] + d[i - 1] * d[k] * d[j];
                if (q < m[i][j]) {
                    m[i][j] = q;
                }
            }
        }
    }
    return m[1][n];
}

int main() {
    int n;
    short d[MAXN];
    freopen("podm.in", "r", stdin);
    freopen("podm.out", "w", stdout);
    cin >> n;
    for (int i = 0; i <= n; i++)
        cin >> d[i];

    cout << matrix_chain_cost(n, d);

    return 0;
}