#include<fstream>
using namespace std;
ifstream fin("podm.in");
ofstream fout("podm.out");
int n;
long long  D[505][505],v[505];
int main(){
    fin>>n;
    n++;
    for(int i=1;i<=n;i++)
        fin>>v[i];
    for(int i=1;i<n;i++)
        D[i][i+1]=0;
    for(int lungime=2;lungime<=n-1;lungime++){
        for(int i=1;i+lungime<=n;i++){
            int j=i+lungime;
            D[i][j]=2000000000;
            for(int k=i+1;k<=j-1;k++)
                D[i][j]=min(D[i][j],D[i][k]+D[k][j]+v[i]*v[j]*v[k]);
        }
    }
    fout<<D[1][n];
    return 0;
}