#include <iostream>
#include <cstdio>
#include <algorithm>
#define nmax 1005
using namespace std;

int d[nmax];
long long cost[nmax][nmax];
int n;

void citire()
{
    scanf("%d", &n);
    for (int i = 1; i <= n+1; i++)
        scanf("%d", &d[i]);
}

int lin(int indx)
{
    return d[indx];
}

int col(int indx)
{
    return d[indx+1];
}
void rezolvare()
{
    int i, j, k, diag;
    for (i = 1; i <= n; i++)
        cost[i][i] = 0;
    for (diag = 2; diag <= n; diag++)
    {
        for (i = 1; i <= n - diag + 1; i++)
        {
            j = i + diag - 1;
            long long minim = 1 << 62;
            for (k = i; k < j; k++)
            {
                long long t = cost[i][k] + cost[k+1][j] + lin(i)*col(k)*col(j);
                if ( t < minim)
                    minim = t;
            }
            cost[i][j] = minim;
        }
    }
}

void debug()
{
    for (int i = 1; i <= n; i++)
    {
        for (int j = 1; j <= n; j++)
            printf("%d\t", cost[i][j]);
        printf("\n");
    }
}
int main()
{
    freopen("podm.in", "r", stdin);
    freopen("podm.out", "w", stdout);

    citire();
    rezolvare();
    cout << cost[1][n];
    //debug();
    return 0;
}