#include <cstdio>
#include <memory.h>
#define INF 0x3f3f3f3f

int n;
long long a[505], b[505][505];

void Citire()
{
    scanf("%d", &n);
    for (int i = 0; i <= n; ++i)
        scanf("%lld", &a[i]);
    /**for (int i = 0; i <= 504; ++i)
        for (int j = 0; j <= 504; ++j)
            b[i][j] = 1 << 63;
    **/
    //memset(b,INF,sizeof(b));
}

long long Min(long long a, long long b)
{
    if (a < b)
        return a;
    return b;
}

void Matrice()
{
    int i, j, k, tz;
    for (i = 1; i <= n; ++i)
        b[i][i] = 0;
    for (tz = 2; tz <= n; ++tz)
        for (i = 1, j = tz; j <= n ; ++i, ++j)
        {
            b[i][j] = ((long long)1<<62);
            for(k = i; k <= j; ++k)
                b[i][j] = Min(b[i][j], b[i][k] + b[k + 1][j] + a[i - 1] * a[j] * a[k]);
        }
    printf("%lld", b[1][n]);

}

int main()
{
    freopen("podm.in", "r", stdin);
    freopen("podm.out", "w", stdout);
    Citire();
    Matrice();
    return 0;
}