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

### Instruction:
How many series originally aired before 1999 with more than 7 episodes and a DVD Region 1 release date of 16 april 2013?

### Inputs:
table_name: table, columns: ['Series Number', 'Number of Episodes', 'Original Air Date', 'DVD Region 2 release date', 'DVD Region 1 release date']

### Response:
SELECT COUNT Series Number FROM table WHERE Original Air Date < 1999 AND Number of Episodes > 7 AND DVD Region 1 release date = 16 april 2013