Resetting serial type after "delete from table"

If I "delete from table", which table contains a serial type field,
and then insert new rows into the table "excluding the [serial] column
from the list of columns in the INSERT statement", the numbers in the
serial column resume where they left off prior to the "delete from
table": 639, 640, 641, 642 for example.

This behavior is totally acceptable, but is it possible to have the
serial column reset itself to 1 following "delete from table" (i.e.
following flushing all the rows from the table)? The only way I can
think to do this is by altering the table by dropping the serial
column and then altering it again by adding a new serial column before
doing the insert. That is only a couple of more lines of script, so I
don't do the work, but is there an easier way?

Thanks,

John