#include <bits/stdc++.h>
using namespace std;
#define lli long long int
#define uli unsigned long long int
#define INF 99999999999
#define rep(i,m,n) for(lli i = m;i < n;i++)
#define rrep(i,m,n) for(lli i=m-1;i>=n;i--)
#define pb(n) push_back(n)
#define UE(N) N.erase(unique(N.begin(),N.end()),N.end());
#define Sort(n) sort(n.begin(), n.end())
#define Rev(n) reverse(n.begin(),n.end())
#define Out(S) cout << S << endl
#define NeOut(S) cout << S
#define HpOut(S) cout << setprecision(20) << S << endl
#define Vecpr(K,L1,L2,N) vector<pair<L1,L2>> K(N)
#define Vec(K,L,N,S) vector<L> K(N,S)
#define DV(K,L,N,M,R) vector<vector<L>> K(N, vector<L>(M,R))
#define pint pair<int,int>
#define Lower(v,X) lower_bound(v.begin(),v.end(),X)-v.begin();
#define mod 1000000007
#define MAX 5100000
#define ceili(x,y) (x+y-1)/y  
#define chmax(a, b) a = (((a)<(b)) ? (b) : (a))
#define chmin(a, b) a = (((a)>(b)) ? (b) : (a))
long long fac[MAX], finv[MAX], inv[MAX];
void COMinit() {
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    inv[1] = 1;
    for (int i = 2; i < MAX; i++){
        fac[i] = fac[i - 1] * i % mod;
        inv[i] = mod - inv[mod%i] * (mod / i) % mod;
        finv[i] = finv[i - 1] * inv[i] % mod;
    }
}
lli nCr(lli n, lli r){
    COMinit();
    if (n < r) return 0;
    if (n < 0 || r < 0) return 0;
    return fac[n] * (finv[r] * finv[n - r] % mod) % mod;
}
int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};
int main(){
  lli A,B,C,D,E,L,R,X,Y,W,H,N,M,K,sum=0,num=0,flag=0;string S,T;
  cin >> N;
  M=nCr(2*N,N);
  Out(M/(1+N));
}