#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define fi first
#define se second
#define MOD 1000000007

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> ii;
typedef vector<ii> vii;
typedef long long ll;
typedef vector<ll> vll;
typedef vector<vll> vvll;
typedef double ld;

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

int n;
unsigned long long dp[505][505];

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    
    fin >> n;
    vector<int> d(n + 1);
    for (auto &val : d) {
        fin >> val;
    }

    for (int i = 0; i <= n; i++) {
        for (int j = 0; j <= n; j++) {
            dp[i][j] = ULLONG_MAX;
        }
    }

    for (int i = 1; i <= n; i++) {
        dp[i][i] = 0;
        if (i < n) {
            dp[i][i + 1] = 1ULL * d[i - 1] * d[i] * d[i + 1];
        }
    }

    for (int len = 2; len <= n; len++) {
        for (int i = 1; i <= n - len + 1; i++) {
            int j = i + len - 1;

            for (int k = i; k < j; k++) {
                unsigned long long new_sol = dp[i][k] + dp[k + 1][j] + 1ULL * d[i - 1] * d[k] * d[j];
                dp[i][j] = min(dp[i][j], new_sol);
            }
        }
    }

    fout << dp[1][n];
    
    fin.close();
    fout.close();
    return 0;
}