#include <bits/stdc++.h>

#define fst(t) std::get<0>(t)
#define snd(t) std::get<1>(t)
#define thd(t) std::get<2>(t)
#define unless(p) if(!(p))
#define until(p) while(!(p))

using ll = std::int64_t;
using P = std::tuple<int,int>;

int N;

int main(){
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    std::cin >> N;

    ll c = 1;
    for(int i=1;i<=N;++i){
        c = c * (2 * N - i + 1) / i;
    }

    c /= N + 1;

    std::cout << c << std::endl;
}