#include <iostream>

#define NMAX 505

using namespace std;

int n;
long long d[NMAX], dp[NMAX][NMAX];

int main()
{
    freopen("podm.in", "r", stdin);
    freopen("podm.out", "w", stdout);
    scanf("%lld", &n);
    for(int i = 0; i <= n; ++i) scanf("%lld", &d[i]);
    for(int i = 1; i <= n; ++i)
        dp[i][i] = 0;
    for(int ln = 2; ln <= n; ++ln)
        for(int i = 1; i <= n - ln + 1; ++i) {
            int j = i + ln - 1;
            dp[i][j] = dp[i][i] + dp[i + 1][j] + d[i - 1] * d[j] * d[i];
            for(int k = i; k <= j - 1; ++k) {
                dp[i][j] = min(dp[i][j], dp[i][k] + dp[k + 1][j] + d[i - 1] * d[k] * d[j]);
            }
        }
    printf("%lld", dp[1][n]);
    return 0;
}