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

### Instruction:
What episode number in the series had a production code of 3x7554?

### Inputs:
table_name: table, columns: ['No. in series', 'No. in season', 'Title', 'Directed by', 'Written by', 'Original air date', 'Production code', 'U.S. viewers (million)']

### Response:
SELECT MIN No. in series FROM table WHERE Production code = 3X7554