#include <bits/stdc++.h>
using namespace std;
const int mod = 1000000007;
int n;
long long up = 1, down = 1;
long long inverse(long long x, long long y) {
  long long ans = 1;
  while (y) {
    if (y & 1) ans = ans * x % mod;
    x = x * x % mod;
    y >>= 1;
  }
  return ans;
}
int main() {
  scanf("%d", &n);
  for (int i = n + 1; i < 2 * n; i++) up = up * i % mod;
  for (int i = 1; i <= n - 1; i++) down = down * i % mod;
  printf("%d\n",
         ((2 * up * inverse(down, (long long)mod - 2)) - n + mod) % mod);
  return 0;
}
