Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
what is  the series number where the date of first broadcast is 16 october 2008?

### Inputs:
table_name: table, columns: ['Series number', 'Episode number', 'Date of first broadcast', 'Total viewers', 'Series average']

### Response:
SELECT Series number FROM table WHERE Date of first broadcast = 16 October 2008