#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("-ffloat-store")
#pragma GCC optimize("-fno-defer-pop")
long long int power(long long int a, long long int b) {
  long long int r = 1;
  while (b > 0) {
    if (b % 2 == 1) {
      r = r * a;
    }
    a = a * a;
    b = b / 2;
  }
  return r;
}
long long int add(long long int a, long long int b) {
  return (1000000007 + (a + b) % 1000000007) % 1000000007;
}
long long int dp[1005][1005][2];
long long int ans = 0;
long long int solve(long long int a, long long int b, long long int flg) {
  if (a == 0 && b == 0) {
    return 0;
  }
  if (a < 0 || b < 0) return 0;
  if (dp[a][b][flg] == -1) {
    if (a == b) {
      if (flg) {
        dp[a][b][flg] = add(1LL, solve(a - 1, b, 0));
      } else {
        dp[a][b][flg] = max(solve(a - 1, b, 1), solve(a - 1, b, 0));
      }
    } else {
      if (flg) {
        long long int m1 = 0;
        long long int m2 = 0;
        if (a != 0) {
          m1 = add(solve(a - 1, b, 0), solve(a, b - 1, 1));
        }
        if (b != 0) {
          m2 = add(solve(a - 1, b, 1), solve(a, b - 1, 0));
        }
        dp[a][b][flg] = add(1LL, max(m1, m2));
      } else {
        dp[a][b][flg] = add(max(solve(a - 1, b, 0), solve(a - 1, b, 1)),
                            max(solve(a, b - 1, 0), solve(a, b - 1, 1)));
      }
    }
  }
  return dp[a][b][flg];
}
int main() {
  std::ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long int n;
  cin >> n;
  memset(dp, -1, sizeof(dp));
  cout << max(solve(n, n, 0), solve(n, n, 1)) << endl;
}
