#include <fstream>

using namespace std;

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

#define NMAX 508
#define LGMAX 208
#define int long long int

struct tip
{
    int v[LGMAX],minim,lgv;
};

int n,i,j,x,cx,aux[LGMAX],lgaux,ov[LGMAX],lgov,nr,k,lg;
pair<int,int>a[NMAX];
tip dp[NMAX][NMAX];

int compar(int a[], int lga, int b[], int lgb);
void adun(int a[], int lga, int b[], int lgb, int rez[], int &lgrez);

signed main()
{
    fin>>n;
    for (i=0; i<=n; i++)
    {
        fin>>x;
        if (i)
        {
            a[i].second=x;
            a[i].first=cx;
        }
        cx=x;
    }
    for (lg=2; lg<=n; lg++)
    {
        for (i=1; i+lg-1<=n; i++)
        {
            dp[i][i+lg-1].lgv=LGMAX-1;
            for (j=i+1; j<=i+lg-1; j++)
            {
                lgaux=1;
                adun(dp[i][j-1].v,dp[i][j-1].lgv,dp[j][i+lg-1].v,dp[j][i+lg-1].lgv,aux,lgaux);
                nr=a[i].first*a[j].first*a[i+lg-1].second;
                lgov=0;
                while (nr)
                {
                    ov[lgov++]=nr%10;
                    nr/=10;
                }
                adun(aux,lgaux,ov,lgov,aux,lgaux);
                if (compar(aux,lgaux,dp[i][i+lg-1].v,dp[i][i+lg-1].lgv)==0)
                {
                    dp[i][i+lg-1].lgv=lgaux;
                    for (k=0; k<dp[i][i+lg-1].lgv; k++)
                    {
                        dp[i][i+lg-1].v[k]=aux[k];
                    }
                }
            }
        }
    }
    for (i=dp[1][n].lgv-1; i>=0; i--)
    {
        fout<<dp[1][n].v[i];
    }
    return 0;
}

void adun(int a[], int lga, int b[], int lgb, int rez[], int &lgrez)
{
    int i,t;
    if (lga<=lgb)
    {
        lgrez=lgb;
        for (i=lga; i<lgb; i++)
        {
            a[i]=0;
        }
    }
    else
    {
        lgrez=lga;
        for (i=lgb; i<lga; i++)
        {
            b[i]=0;
        }
    }
    for (t=i=0; i<lgrez; i++)
    {
        int val=t+a[i]+b[i];
        rez[i]=val%10;
        t=val/10;
    }
    if (t)
    {
        rez[lgrez++]=t;
    }
}

int compar(int a[], int lga, int b[], int lgb)/// 0 daca a e mai mic 1 daca a e mai mare
{
    int i;
    if (lga<lgb)
    {
        return 0;
    }
    if (lga>lgb)
    {
        return 1;
    }
    for (i=lga-1; i>=0; i--)
    {
        if (a[i]<b[i])
        {
            return 0;
        }
        if (a[i]>b[i])
        {
            return 1;
        }
    }
    return 1;
}