#include <bits/stdc++.h>
using namespace std;
int mod = 1000000007;
long long rev(int k, int mod) {
  int n = mod - 2;
  long long res = 1;
  while (n) {
    if (n & 1) res = (res * k) % mod;
    k = (k * 1ll * k) % mod;
    n >>= 1;
  }
  return res;
}
int C(int n, int k) {
  if (k == 0) return 1;
  int x = C(n - 1, k - 1);
  x = (x * 1ll * n) % mod;
  return (x * 1ll * rev(k, mod)) % mod;
}
int main() {
  int n;
  cin >> n;
  cout << (C(2 * 1ll * n, n) - n + mod) % mod << endl;
  return 0;
}
