#include <bits/stdc++.h>
using namespace std;
bitset<3002> viz;
int main() {
  int N, x;
  scanf("%d", &N);
  for (int i = 1; i <= N; ++i) {
    scanf("%d", &x);
    viz[x] = 1;
  }
  for (int i = 1; i <= 3002; ++i)
    if (!viz[i]) {
      printf("%d", i);
      return 0;
    }
  return 0;
}
