How  many of the  series # when the original airdate is september 25, 1967?
CREATE TABLE table_21146729_6 (series__number VARCHAR, original_airdate VARCHAR)
SELECT COUNT(series__number) FROM table_21146729_6 WHERE original_airdate = "September 25, 1967"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_21146729_6 (series__number VARCHAR, original_airdate VARCHAR) Question: How  many of the  series # when the original airdate is september 25, 1967? [/INST] SELECT COUNT(series__number) FROM table_21146729_6 WHERE original_airdate = "September 25, 1967" </s>