user: Question: what is  the series number where the date of first broadcast is 16 October 2008?
Columns: ['Series number', 'Episode number', 'Date of first broadcast', 'Total viewers', 'Series average']
Types: ['text', 'real', 'text', 'real', 'real']
Sample row: ['Series 1', 1.0, '27 September 2007', 1997000.0, 1242125.0]
SQL:

assistant: SELECT "Series number" FROM "Table" WHERE "Date of first broadcast" = '16 October 2008';