SCHEMA:
CREATE TABLE table_12995531_3 (total_viewers INTEGER, date_of_first_broadcast VARCHAR, episode_number VARCHAR)
USER:
what is the total viewers where the date of first broadcast is 28 january 2010 and the episode number is 1?

QUERY:
SELECT MIN(total_viewers) FROM table_12995531_3 WHERE date_of_first_broadcast = "28 January 2010" AND episode_number = 1