#include <bits/stdc++.h>
using namespace std;
long long dp[1010][1010];
long long sum[2010];
const int M = 1e9 + 7;
int main() {
  int n;
  while (cin >> n) {
    memset(dp, 0, sizeof(dp));
    memset(sum, 0, sizeof(sum));
    dp[0][0] = 1;
    sum[0] = 1;
    for (int d = 1; d <= 2 * n; d++) {
      sum[d] = 0;
      for (int l = 1; l <= n; l++) {
        int r = d - l;
        if (r > l || r < 0) continue;
        dp[l][r] = dp[l - 1][r];
        if (r > 0) dp[l][r] = (dp[l][r] + dp[l][r - 1]) % M;
        sum[d] = (sum[d] + dp[l][r]) % M;
      }
    }
    long long res = 0;
    for (int d = 2 * n; d >= 1; d -= 2) {
      res = (res + sum[d - 1]) % M;
    }
    cout << res << endl;
  }
  return 0;
}
