#include <iostream>
using namespace std;
int main()
{
int n;
long long p = 1;
cin >> n; // 1 <= n <= 16
for(int i=2; i<=2*n; i+=2) p*=i;
cout << p;
return 0;
}
#include <iostream>
using namespace std;
int main()
{
int n;
long long p = 1;
cin >> n; // 1 <= n <= 16
for(int i=2; i<=2*n; i+=2) p*=i;
cout << p;
return 0;
}