#include<bits/stdc++.h>
using namespace std;
using Int = long long;
template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}
template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;}

//INSERT ABOVE HERE
signed main(){
  Int n;
  cin>>n;
  Int ans=1;
  for(Int i=n;i<n*2;i++) ans*=i+1;
  for(Int i=0;i<n+1;i++) ans/=i+1;
  cout<<ans<<endl;
  return 0;
}