#include <cstdio>

using namespace std;

int a[505];
long long dp[505][505];

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

    int n;
    long long aux;
    scanf("%d", &n);

    for(int i = 0; i <= n; ++ i) {
        scanf("%d", &a[i]);
    }

    for(int j = 2; j <= n; ++ j) {
        for(int i = j - 1; i >= 1; -- i) {
            dp[i][j] = -1;
            for(int k = i; k < j; ++ k) {
                aux = dp[i][k] + dp[k + 1][j] + (long long) a[i - 1] * a[j] * a[k];
                if(dp[i][j] == -1 || aux < dp[i][j]) {
                    dp[i][j] = aux;
                }
            }
        }
    }

    printf("%lld", dp[1][n]);

    return 0;
}