PL/SQL :: Updating Column Value If Any DML Operations Done

I created a table with a column "id" and values for this column is attached a sequence. And now i need, if any value deleted from the table the column "id" will need to be sequence.

ex:

id name
-- -------
1 xxxx
2 yyyy
3 zzzzz
4 pppp
5 rrrrrr

if i delete

delete from test where id=4;

then automatically.. "id" column values will again in sequence... like this

id name
-- -------1 xxxxx
2 yyyyy
3 zzzzzz
4 rrrrrr

note: in the above if i delete the id=4 from the table again it will have be in sequence and if i inserted the again it has to take the next value continue to sequence....

ex : insert to test values(seq_name.nextval,'tttt');

id name
-- -------
1 xxxxx
.
.
.
4 rrrrr
5 ttttt