#include <bits/stdc++.h>
using namespace std;
void debug_out() { cerr << endl; }
template <class T>
ostream& prnt(ostream& out, T v) {
  out << v.size() << '\n';
  for (auto e : v) out << e << ' ';
  return out;
}
template <class T>
ostream& operator<<(ostream& out, vector<T> v) {
  return prnt(out, v);
}
template <class T>
ostream& operator<<(ostream& out, set<T> v) {
  return prnt(out, v);
}
template <class T1, class T2>
ostream& operator<<(ostream& out, map<T1, T2> v) {
  return prnt(out, v);
}
template <class T1, class T2>
ostream& operator<<(ostream& out, pair<T1, T2> p) {
  return out << '(' << p.first << ' ' << p.second << ')';
}
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
  cerr << " " << H;
  debug_out(T...);
}
const int N = 2019;
const int MOD = 1e9 + 7;
int n, dp[N][N], ans[2];
bool valid(int level, int diff) {
  if (diff < 0) return 0;
  if (2 * n - level < diff) return 0;
  return 1;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin >> n;
  dp[1][1] = 1;
  ans[0] = 1;
  for (int i = 1; i <= 2 * n; i++) {
    for (int j = 0; j <= n; j++) {
      ans[i % 2] = (ans[i % 2] + dp[i][j]) % MOD;
      if (valid(i + 1, j + 1))
        dp[i + 1][j + 1] += dp[i][j], dp[i + 1][j + 1] %= MOD;
      ;
      if (valid(i + 1, j - 1))
        dp[i + 1][j - 1] += dp[i][j], dp[i + 1][j - 1] %= MOD;
    }
  }
  cout << ans[1] << '\n';
}
