Table: tvb_series_1998
Columns: airing_date
english_title_chinese_title
number_of_episodes
genre
official_website

Question: What is the lowest number of episodes in a series with an airing date of 12 jan- 6 feb?
SQL: SELECT MIN("number_of_episodes") FROM tvb_series_1998 WHERE "airing_date" = '12 jan- 6 feb'