#include <cstdio> #include <cmath> #include <cstring> #include <ctime> #include <iostream> #include <algorithm> #include <set> #include <vector> #include <sstream> #include <typeinfo> #include <fstream> #include <climits> #include <functional> #define REP(i,n) for(int i = 0;i < n;i++) using namespace std; typedef long long ll; const int INF = INT_MAX / 4; const int p = 1e9 + 7; const ll inv_elem_2 = 500000004; int main(void) { cin.tie(0); ios::sync_with_stdio(false); int N; cin >> N; ll res = 1; for(int i = 2;i <= N * 2;i++) { res = (res * i) % p; } REP(i, N) res = (res * inv_elem_2) % p; cout << res << "\n"; return 0; }