CREATE TABLE table_name_19 (number_in_series INT, production_code VARCHAR)

What is the series number that has a production code of 50021 50025?
SELECT MAX(number_in_series) FROM table_name_19 WHERE production_code = "50021–50025"
SELECT MAX("number_in_series") FROM "table_name_19" WHERE "50021–50025" = "production_code"