#include <bits/stdc++.h>
using namespace std;
long long n, a = 1, b = 1, inv;
inline long long Pow(long long d, long long p) {
  long long res = 1;
  while (p > 0) {
    if (p & 1) res = ((res * d) % 1000000007);
    d = ((d * d) % 1000000007);
    p >>= 1;
  }
  return res;
}
int main() {
  cin >> n;
  for (int i = 1; i <= n * 2; i++) a = ((a * i) % 1000000007);
  for (int i = 1; i <= n; i++) {
    b = ((b * i) % 1000000007);
    b = ((b * i) % 1000000007);
  }
  inv = Pow(b, 1000000005);
  a = ((a * inv) % 1000000007);
  cout << ((a - n + 1000000007) % 1000000007) << endl;
  return 0;
}
