#include <iostream>
#include <fstream>
using namespace std;
ifstream in("podm.in");
ofstream out("podm.out");
const long long MAX_LONG_LONG = 1000000000000000000;
int main()
{
    long long  n,d[501],cost[501][501];
    in >> n;
    for(int i = 1 ; i <= n+1 ;  i++)
        in >> d[i-1],cost[i][i] = 0;
    cost[n][n] = 0;
    for(int gap =  1 ; gap <= n -1; gap++)
        for(int i = 1 ; i <= n - gap  ; i++)
        {
             int j = i + gap ;
             long long  costul = MAX_LONG_LONG;
             for(int k = i ; k <= j-1 ; k++)
                costul = min(costul,cost[i][k] + cost[k+1][j] + d[i-1]*d[k]*d[j]);
             cost[i][j] = costul;
        }
    out<<cost[1][n];
    return 0;
}