#include <bits/stdc++.h>
using namespace std;
long long MOD = 1e9 + 7, n, k = 1, i, j;
long long ppow(long long a) {
  long long ans = 1, b = MOD - 2;
  while (b) {
    if (b & 1) ans = ans * a % MOD;
    b /= 2;
    a = a * a % MOD;
  }
  return ans;
}
int main() {
  scanf("%I64d", &n);
  for (i = 1, j = 2 * n - 1; i <= n; i++, j--) k = k * j % MOD * ppow(i) % MOD;
  printf("%I64d\n", (2 * k - n + MOD) % MOD);
  return 0;
}
