#include <bits/stdc++.h>
using namespace std;
const int N = 1003, MOD = 1e9 + 7;
int n, memo[N][N][2];
int go(int x, int y, int state) {
  if (x == y && x == n) return 0;
  int &ret = memo[x][y][state];
  if (ret != -1) return ret;
  int take1_leave2 = 0, leave1_take2 = 0, leave_both = 0;
  if (x < n) {
    int leave1 = go(x + 1, y, 0);
    leave1_take2 += leave1;
    leave_both += leave1;
    if (state == 0) {
      take1_leave2 += 1 + go(x + 1, y, 1);
    }
  }
  if (y < x) {
    int leave2 = go(x, y + 1, 0);
    take1_leave2 += leave2;
    leave_both += leave2;
    if (state == 0) {
      leave1_take2 += 1 + go(x, y + 1, 1);
    }
  }
  ret = max(take1_leave2, max(leave1_take2, leave_both)) % MOD;
  return ret;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(NULL), cout.tie(NULL);
  cin >> n;
  memset(memo, -1, sizeof memo);
  cout << go(0, 0, 0);
  return 0;
}
