#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  vector<int> vec(3002);
  for (int i = 0; i < n; ++i) {
    int a;
    cin >> a;
    vec[a]++;
  }
  for (int i = 1; i <= 3001; ++i) {
    if (!vec[i]) {
      cout << i << endl;
      return 0;
    }
  }
  return 0;
}
