#include<cstdio>
#include<fstream>
#define LL long long
using namespace std;
int n;
LL a[1<<9],d[1<<9][1<<9];
ifstream f("podm.in");
void read()
{
    freopen("podm.out","w",stdout);
    f>>n;
    for(int i=1;i<=n+1;i++)
        f>>a[i];
}
inline LL min(LL x,LL y)
{
    return x<y?x:y;
}
void solve()
{
    long long q;
    for(int i=n;i>=1;i--)
    {
        d[i][i]=0;
        d[i][i+1]=a[i]*a[i+1]*a[i+2];
        for(int j=i+2;j<=n;j++)
        {
            d[i][j]=d[i][i]+d[i+1][j]+(LL)a[i]*a[i+1]*a[j+1];
            for(int k=i+1;k<=j;k++)
            {
                q=d[i][k]+d[k+1][j]+a[i]*a[k+1]*a[j+1];
                if(q<d[i][j])
                    d[i][j]=q;
            }
        }
    }

}
int main()
{
    read();
    solve();
    printf("%lld",d[1][n]);
    return 0;
}