#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3ffffff;
const long long LL_INF = 0x3fffffffffffffffll;
const int MOD = 1e9 + 7;
const long long HASH_KEY = 6151;
const long long HASH_MOD = 1610612741;
const int MAXN = 1003;
pair<int, bool> f[MAXN * 2][MAXN];
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int n;
  cin >> n;
  int m = 2 * n;
  auto sum = [&](int a, int b) {
    a += b;
    if (a >= MOD) {
      a -= MOD;
    }
    return a;
  };
  f[0][0] = make_pair(0, true);
  for (int i = int(1); i < int(m + 1); ++i)
    for (int j = int(0); j < int(min(i, n) + 1); ++j) {
      int s = 0;
      bool flag = false;
      if (j > 0) {
        s = sum(s, f[i - 1][j - 1].first);
        flag |= f[i - 1][j - 1].second;
      }
      if (j + 1 <= i - 1) {
        s = sum(s, f[i - 1][j + 1].first);
        flag |= f[i - 1][j + 1].second;
      }
      f[i][j] = make_pair(sum(s, flag ? 1 : 0), !flag);
    }
  cout << f[m][0].first << "\n";
  return 0;
}
