#include <bits/stdc++.h>
using namespace std;
const int P = 1e9 + 7, INF = 0x3f3f3f3f;
long long gcd(long long a, long long b) { return b ? gcd(b, a % b) : a; }
long long qpow(long long a, long long n) {
  long long r = 1 % P;
  for (a %= P; n; a = a * a % P, n >>= 1)
    if (n & 1) r = r * a % P;
  return r;
}
long long inv(long long first) {
  return first <= 1 ? 1 : inv(P % first) * (P - P / first) % P;
}
inline int rd() {
  int first = 0;
  char p = getchar();
  while (p < '0' || p > '9') p = getchar();
  while (p >= '0' && p <= '9') first = first * 10 + p - '0', p = getchar();
  return first;
}
const int N = 4e3 + 10;
int n, dp[N][N];
int main() {
  scanf("%d", &n);
  dp[0][0] = 1;
  int ans = 0;
  for (int i = 0; i <= 2 * n; ++i) {
    for (int j = 0; j <= i; ++j) {
      (dp[i + 1][j + 1] += dp[i][j]) %= P;
      if (j) (dp[i + 1][j - 1] += dp[i][j]) %= P;
      if (2 * n - i >= j && i % 2 == 1) (ans += dp[i][j]) %= P;
    }
  }
  printf("%d\n", ans);
}
