CREATE TABLE table_23176 ("Episode #" FLOAT, "Prod #" FLOAT, "Title" CLOB, "Directed by" CLOB, "Written by" CLOB, "Originalairdate" CLOB, "Filmed" CLOB)

What was the production number of the episode filmed in aug/sept 1968?
SELECT "Prod #" FROM table_23176 WHERE "Filmed" = 'Aug/Sept 1968'
SELECT "Prod #" FROM "table_23176" WHERE "Filmed" = 'Aug/Sept 1968'