#include <bits/stdc++.h>
using std::abs;
using std::array;
using std::cerr;
using std::cin;
using std::cout;
using std::generate;
using std::get;
using std::make_pair;
using std::make_tuple;
using std::map;
using std::max;
using std::max_element;
using std::min;
using std::min_element;
using std::pair;
using std::reverse;
using std::set;
using std::sort;
using std::string;
using std::swap;
using std::tuple;
using std::unique;
using std::vector;
template <typename T>
T input() {
  T res;
  cin >> res;
  {};
  return res;
}
template <typename IT>
void input_seq(IT b, IT e) {
  std::generate(b, e,
                input<typename std::remove_reference<decltype(*b)>::type>);
}
const int mod = 1000 * 1000 * 1000 + 7;
int add(int a, int b) { return (a + b >= mod ? a + b - mod : a + b); }
const int max_n = 1001;
pair<int, bool> dp[2 * max_n][2 * max_n];
int main() {
  std::iostream::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
  int n = input<int>();
  n *= 2;
  assert(n / 2 < max_n);
  dp[0][0] = make_pair(0, true);
  for (int len = 1; len <= n; ++len) {
    for (int bal = 0; bal <= len; ++bal) {
      int sum = 0;
      bool has = false;
      if (bal != 0) {
        sum = add(sum, dp[len - 1][bal - 1].first);
        has = has or dp[len - 1][bal - 1].second;
      }
      if (bal + 1 <= len - 1) {
        sum = add(sum, dp[len - 1][bal + 1].first);
        has = has or dp[len - 1][bal + 1].second;
      }
      if (has)
        dp[len][bal] = make_pair(add(sum, 1), false);
      else
        dp[len][bal] = make_pair(sum, true);
    }
  }
  cout << dp[n][0].first << "\n";
  return 0;
}
