#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  vector<bool> arr(3001, false);
  for (int i = 0; i < n; i++) {
    int temp;
    cin >> temp;
    arr[temp] = true;
  }
  int res = -1;
  for (int i = 1; i <= 3000; i++) {
    if (arr[i] == false) {
      res = i;
      break;
    }
  }
  if (res == -1) {
    cout << 3001 << endl;
  } else {
    cout << res << endl;
  }
  return 0;
}
