#include <fstream>
#define For(i,a,b) for(int i=a;i<=b;i++)
#define inf 50000000000ll
using namespace std;
ifstream f("podm.in");
ofstream g("podm.out");
int n,i,j,k,l;
long long d[502];
long long a[505][505];
int main()
{   f>>n;
    For(i,1,n+1)
        f>>d[i];
    For(i,1,n)
    For(j,i+1,n)
        a[i][j]=inf;
    For(i,1,n-1)
        a[i][i+1]=d[i]*d[i+1]*d[i+2];
    For(l,3,n)
    For(i,1,n){
        j=i+l-1;
        For(k,i,j){
            a[i][j]=min(a[i][j],d[i]*d[k+1]*d[j+1]+a[i][k]+a[k+1][j]);
        }
    }
    g<<a[1][n];
    return '\0';
}