#include <bits/stdc++.h>
using namespace std;
const int mod = 1e9 + 7;
long long int dp[1001][1001][2];
int main() {
  int n;
  cin >> n;
  for (int i = 0; i <= n; i++) {
    for (int j = i; j <= n; j++) {
      if (i > 0) dp[i][j][0] = (dp[i][j][0] + dp[i - 1][j][1]) % mod;
      if (j > i) dp[i][j][0] = (dp[i][j][0] + dp[i][j - 1][1]) % mod;
      if (i == 0) {
        if (j > i) dp[i][j][1] = (dp[i][j][1] + dp[i][j - 1][0] + 1) % mod;
      } else if (i == j) {
        dp[i][j][1] = (dp[i][j][1] + dp[i - 1][j][0] + 1) % mod;
      } else {
        dp[i][j][1] =
            (dp[i][j][1] + dp[i - 1][j][0] + dp[i][j - 1][1] + 1) % mod;
      }
    }
  }
  cout << dp[n][n][1] << endl;
}
