#include <bits/stdc++.h>
using namespace std;
long long n;
long long f[1005][1005];
long long ans;
int main() {
  scanf("%lld", &n);
  f[0][0] = 1;
  for (long long i = 1; i <= n; ++i) {
    for (long long j = 0; j <= i; ++j) {
      f[i][j] = (f[i - 1][j] + f[i][j - 1]) % 1000000007;
    }
  }
  for (long long i = 1; i <= n; ++i) {
    for (long long j = 0; j <= i; ++j) {
      if ((i + j) & 1) ans = (ans + f[i][j]) % 1000000007;
    }
  }
  printf("%lld\n", ans);
  return 0;
}
