#include <bits/stdc++.h>
const int mod = 1e9 + 7;
int main() {
  std::ios::sync_with_stdio(false);
  std::cin.tie(nullptr);
  std::cout.tie(nullptr);
  int n;
  std::cin >> n;
  n *= 2;
  std::vector<std::vector<int>> dp(n + 1, std::vector<int>(n + 1, 0));
  dp[0][0] = 1;
  for (int i = 1; i <= n; ++i) {
    for (int j = 0; j <= n; ++j) {
      dp[i][j + 1] = (dp[i][j + 1] + dp[i - 1][j]) % mod;
      if (j) dp[i][j - 1] = (dp[i][j - 1] + dp[i - 1][j]) % mod;
    }
  }
  int ans = 0;
  for (int i = 1; i <= n; i += 2) {
    for (int j = 0; j <= i && j <= n - i; ++j) {
      ans = (ans + dp[i][j]) % mod;
    }
  }
  std::cout << ans << '\n';
  return 0;
}
