//test #include<bits/stdc++.h> using namespace std; long long n,ans[25]={ 1, 2, 5, 14, 42, 132, 429, 1430, 4862, 16796, 58786, 208012, 742900, 2674440, 9694845, 35357670, 129644790, 477638700, 1767263190, 6564120420, 24466267020, 91482563640, 343059613650, 1289904147324, 4861946401452 }; int main(){ while(cin>>n)cout<<ans[n-1]<<endl; return 0; }