#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

int main() {
    int n;
    cin>>n;
    ll c[n+1];
    c[0]=c[1]=1;
    for (int i=2;i<=n;i++)
        c[i]=c[i-1]*(4*i-2)/(i+1);
    cout<<c[n]<<endl;
    return 0;
}