#include <bits/stdc++.h>
using namespace std;
int32_t main() {
  int n;
  int x;
  int i;
  int sol[3005] = {0};
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> x;
    sol[x]++;
  }
  for (int i = 1; i <= 3005; i++) {
    if (sol[i] == 0) {
      cout << i << endl;
      break;
    }
  }
  return 0;
}
