#include
using namespace std;
// A recursive function to find nth catalan number
unsigned long int catalan(unsigned int n)
{
// Base case
if (n <= 1)
return 1;
// catalan(n) is sum of
// catalan(i)*catalan(n-i-1)
unsigned long int res = 0;
for (int i = 0; i < n; i++)
res += catalan(i)
* catalan(n - i - 1);
return res;
}
// Driver code
int main()
{
int n;
cin>>n;
cout << catalan(n) << endl;
return 0;
}