#include <bits/stdc++.h>
using namespace std;
int a[3100];
int n, m, i;
int main() {
  cin >> n;
  memset(a, 0, sizeof(a));
  for (i = 1; i <= n; i++) {
    cin >> m;
    a[m] = 1;
  }
  for (i = 1; i <= 3001; i++)
    if (a[i] == 0) {
      cout << i << endl;
      break;
    }
  return 0;
}
