#include <bits/stdc++.h>
using namespace std;
const int maxn = 1005;
const int mod = 1e9 + 7;
int dp[maxn * 2][maxn];
int cnt[maxn * 3];
inline int add(int a, int b) {
  a += b;
  if (a >= mod) a -= mod;
  return a;
}
int main(void) {
  int n;
  scanf("%d", &n);
  dp[0][0] = 1;
  for (int i = 1; i <= 2 * n; i++) {
    for (int j = 0; j <= i; j++) {
      if (2 * n < i + j) continue;
      if (j)
        dp[i][j] = add(dp[i - 1][j + 1], dp[i - 1][j - 1]);
      else
        dp[i][j] = dp[i - 1][j + 1];
      cnt[i] = add(cnt[i], dp[i][j]);
    }
  }
  int res = 0;
  for (int i = 1; i <= 2 * n; i += 2) res = add(res, cnt[i]);
  printf("%d\n", res);
  return 0;
}
