如何找出一个连续序列中的断号

一个连续的数字序列，中间有几个断号，如何找出这些断号？

select">SYS@ning>select * from test order by id;

ID
----------
1
2
5
6
9
10
11
14

8 rows selected.

select">SYS@ning>select level from dual connect by level<=(select max(id) from test)
2 minus
3 select id from test;

LEVEL
----------
3
4
7
8
12
13

6 rows selected.