#include <bits/stdc++.h>

using namespace std;

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

long long dp[502][502];
int v[502];

int main() {
    int n;
    fin >> n;
    n += 1;
    for (int i = 1; i <= n; ++i) {
        fin >> v[i];
    }
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= n; ++j) {
            dp[i][j] = 1000000000000000;
        }
    }
    for (int i = 1; i < n; ++i) {
        dp[i][i + 1] = 0;
    }
    for (int i = n; i >= 1; --i) {
        for (int j = i + 2; j <= n; ++j) {
            for (int k = i + 1; k <= j - 1; ++k) {
                dp[i][j] = min(dp[i][j], dp[i][k] + dp[k][j] + 1LL * v[i] * v[j] * v[k]);
            }
        }
    }
    fout << dp[1][n];
    return 0;
}