#include <fstream>
#include <iostream>
#include <vector>
#include <bitset>
#include <string.h>
#include <algorithm>
#include <iomanip>
#include <math.h>
#include <time.h>
#include <stdlib.h>
#include <set>
#include <map>
#include <string>
#include <queue>
#include <deque>

using namespace std;

const char infile[] = "podm.in";
const char outfile[] = "podm.out";

ifstream fin(infile);
ofstream fout(outfile);

const int MAXN = 505;
const int oo = 0x3f3f3f3f;

typedef vector<int> Graph[MAXN];
typedef vector<int> :: iterator It;

const inline int min(const int &a, const int &b) { if( a > b ) return b;   return a; }
const inline int max(const int &a, const int &b) { if( a < b ) return b;   return a; }
const inline void Get_min(int &a, const int b)    { if( a > b ) a = b; }
const inline void Get_max(int &a, const int b)    { if( a < b ) a = b; }

long long dp[MAXN][MAXN];
int d[MAXN], N;

int main() {
    fin >> N;
    for(int i = 0 ; i <= N ; ++ i)
        fin >> d[i];
    memset(dp, oo, sizeof(dp));
    for(int i = 1 ; i <= N ; ++ i)
        dp[i][i] = 0;
    for(int i = 1 ; i < N ; ++ i)
        dp[i][i + 1] = 1LL * d[i - 1] * d[i] * d[i + 1];
    for(int i = N ; i >= 1 ; -- i)
        for(int j = i + 1 ; j <= N ; ++ j)
            for(int k = i ; k < j ; ++ k)
                dp[i][j] = min(dp[i][j], 1LL * dp[i][k] + dp[k + 1][j] + 1LL * d[i - 1] * d[j] * d[k]);
    fout << dp[1][N] << '\n';
    fin.close();
    fout.close();
    return 0;
}