//ALEX ENACHE

#include <vector>
#include <algorithm>
#include <queue>
#include <map>
#include <set>
#include <unordered_map>
#include <time.h>
#include <iomanip>
#include <deque>
#include <math.h>
#include <cmath>
#include <assert.h>
#include <stack>
#include <bitset>
#include <random>
#include <chrono>

using namespace std;

const double PI = acos(-1);
const double eps = 1e-6;

inline long long lgput(long long a , long long b , long long mod) {
    long long ret = 1;
    while( b ){
        if(b & 1) ret = (ret * a) % mod;
        a = (a * a) % mod;
        b >>= 1;
    }

    return (ret%mod);
}

inline long long inv(long long x , long long MOD) {
    return lgput(x, MOD - 2, MOD);
}

inline bool exist (double nr){
    return (nr < -eps) || (nr > eps);
}

int big_rand(){
    return rand () * RAND_MAX + rand();
}

//-----------------------------------------------------------------

//#include <iostream>
#include <fstream>
ifstream cin ("podm.in");ofstream cout ("podm.out");

pair < long long , long long > v[510];
int aux[510];

long long dp[510][510];
const long long inf = 1e18;

int main() {

    //freopen("input", "r", stdin);freopen("output", "w", stdout);

    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    cout << setprecision(10) << fixed;
    mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
    srand(time(nullptr));

    int n;
    cin>>n;
    for (int i=1; i<=n+1; i++){
        cin>>aux[i];
    }
    for (int i=1; i<=n; i++){
        v[i] = {aux[i] , aux[i+1]};
    }

    for (int l=2; l<=n; l++){
        for (int i=1; i<=n; i++){
            dp[i][l] = inf;
            int j = i+l-1;
            for (int l1=1; l1<l; l1++){
                int l2 = l-l1;
                int k = i + l1;
                dp[i][l] = min(dp[i][l] , dp[i][l1] + dp[k][l2] + v[i].first * v[k].first * v[j].second);
            }
        }
    }

    cout<<dp[1][n];


    return 0;
}