What episode aired on 18 April 2007?
CREATE TABLE table_10749367_3 (_number INTEGER, air_date VARCHAR)
SELECT MIN(_number) FROM table_10749367_3 WHERE air_date = "18 April 2007"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_10749367_3 (_number INTEGER, air_date VARCHAR) Question: What episode aired on 18 April 2007? [/INST] SELECT MIN(_number) FROM table_10749367_3 WHERE air_date = "18 April 2007" </s>