#include <bits/stdc++.h>
using namespace std;
int s, n;
int main() {
  scanf("%d", &n);
  int freq[3005];
  memset(freq, 0, sizeof(freq));
  for (int i = 0; i < n; i++) {
    int x;
    scanf("%d", &x);
    freq[x]++;
  }
  for (int i = 1; i <= 3001; i++) {
    if (!freq[i]) {
      printf("%d\n", i);
      return 0;
    }
  }
  return 0;
}
