#include <iostream>
#include <fstream>

using namespace std;

ifstream fin("podm.in");
ofstream fout("podm.out");
int main()
{
    int n, i, j, L, v[505], k;
    unsigned long long d[505][505];
    fin >> n; n++;
    for(i = 1; i <= n; i++)
    {
        fin >> v[i];
        d[i][i+1] = 0;
    }
    for(L = 3; L <= n; L++)
    {
        for(i = 1; i + L - 1 <= n; i++)
        {
            j = i + L - 1;
            d[i][j] = 9223372036854775800 * 2;
            for(k = i + 1; k <= j - 1; k++)
            {
                d[i][j] = min(d[i][j], v[i]*v[k]*v[j] + d[i][k] + d[k][j]);
            }
        }
    }
    fout << d[1][n];
    return 0;
}