#include <fstream>
#define DIM 510
#include <climits>
#define INF 1e18

using namespace std;

ifstream fin ("podm.in");
ofstream fout("podm.out");

int n,l,d[DIM];
long long dp[DIM][DIM];
int i,j;
int main()
{
    fin>>n;
    for(i=1;i<=n+1;i++)
        fin>>d[i];
    for(i=1;i<n;i++)
        dp[i][i+1]=1LL*d[i]*d[i+1]*d[i+2];
    for(l=3;l<=n;l++)
    {
        for(i=1;i<=n-l+1;i++)
        {
            j=i+l-1;
            dp[i][j]=INF;
            for(int k=i;k<=j;k++)
                dp[i][j]=min(dp[i][j],dp[i][k]+dp[k+1][j]+1LL*d[i]*d[k+1]*d[j+1]);
        }
    }
    fout<<dp[1][n];
    return 0;
}