#include<stdio.h>
#include<algorithm>

using namespace std;

#define NMAX 502
#define INF 2000000000000000000

int n, v[NMAX];
unsigned long long dp[NMAX][NMAX];

int main()
{
    freopen("podm.in", "r", stdin);
    freopen("podm.out", "w", stdout);

    int lim;

    scanf("%d", &n);
    ++n;

    for(int i=1; i<=n; ++i)
        scanf("%d", &v[i]);

    for(int i=0; i<=n; ++i)
    {
        dp[i][i]=0;
        for(int j=i+1; j<=n; ++j)
            dp[i][j]=INF;
    }

    for(int l=2; l<n; ++l)
    {
        for(int i=1, j=l; j<n; ++i, ++j)
        {
            for(int k=i; k<j; ++k)
            {
                dp[i][j]=min(dp[i][j], dp[i][k]+(unsigned long long)v[i]*v[j+1]*v[k+1]+dp[k+1][j]);
            }
        }
    }

    printf("%llu\n", dp[1][n-1]);

    return 0;
}