#include <iostream>
#include <fstream>

using namespace std;

const long long int INF=9223372036854775807;
long long int m[505][505];

int main()
{
    ifstream fin ("podm.in");
    ofstream fout ("podm.out");
    int n,d[505];
    fin>>n;
    for (int i=0; i<n+1; i++)
        fin>>d[i];
    for (int i=1; i<=n-1; i++)
        m[i][i+1]=1LL*d[i-1]*d[i]*d[i+1];
    for (int diag=2; diag<=n-1; diag++)
        for (int i=1; i<=n-diag; i++)
        {
            int j=i+diag;
            m[i][j]=INF;
            for (int k=i; k<=j-1; k++)
                m[i][j]=min(m[i][j],m[i][k]+m[k+1][j]+1LL*d[i-1]*d[k]*d[j]);
        }
    fout<<m[1][n];
    return 0;
}