is it possible without using union ?

I have to get a query like this:

for examaple : there is a number pool   - range is from 1 to 100

and I have 3 records in a table that has numbers taken from this number
pool.

for example.. in table I have 3 records... and all NUMBER field values are
1,2,3...

and than I want to list unreserved list of queries.
like

(if 1,2,3 are in records already in table.)
----------------
4
5
6
...
...
...
100
------------------------
I want to get the number range list except the recorded ones


is it possible by someway ? only via msSQL  solutions

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