#include <bits/stdc++.h>
int main() {
  bool check[3003] = {0};
  int n, m, i;
  scanf("%d", &n);
  for (i = 0; i < n; i++) {
    scanf("%d", &m);
    check[m] = 1;
  }
  for (i = 1; i < 3003; i++)
    if (check[i] != 1) {
      printf("%d\n", i);
      break;
    }
  return 0;
}
