#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, a;
  cin >> n;
  int arr[3005] = {0};
  for (int i = 0; i < n; i++) {
    cin >> a;
    arr[a]++;
  }
  int f = 0;
  for (int i = 1; i <= 3001; i++) {
    if (arr[i] == 0) {
      cout << i;
      return 0;
    }
  }
}
