#include <bits/stdc++.h>
using namespace std;
long long mod = 1e9 + 7;
long long gcdExtended(long long a, long long b, long long &x, long long &y) {
  if (a == 0) {
    x = 0, y = 1;
    return b;
  }
  long long gcd = gcdExtended(b % a, a, y, x);
  x -= (b / a) * y;
  return gcd;
}
long long modInverse(long long b, long long m) {
  long long x, y;
  long long g = gcdExtended(b, m, x, y);
  if (g != 1) return -1;
  return (x % m + m) % m;
}
long long modDivide(long long a, long long b, long long m) {
  a %= m;
  long long inv = modInverse(b, m);
  return (inv * a) % m;
}
long long ncr(long long x, long long y) {
  long long ans = 1;
  for (long long i = 0; i < min(y, x - y); i++) {
    ans = (ans * (x - i)) % mod;
    ans = modDivide(ans, i + 1, mod);
  }
  return ans % mod;
}
int main() {
  ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  long long n;
  cin >> n;
  cout << (ncr(n * 2, n)) % mod - n;
  return 0;
}
