#include <bits/stdc++.h>
using namespace std;
int n, a[3001], b[3001], cnt = 1, sum;
int main() {
  cin >> n;
  for (int i = 1; i <= n; i++) cin >> a[i];
  sort(a + 1, a + n + 1);
  while (1) {
    if (cnt == a[++sum])
      cnt++;
    else {
      cout << cnt;
      return 0;
    }
  }
  return 0;
}
