Question: Which leagues entered in rounds where there were 16 winners from the previous round?
Schema: create table table_23449363_1 (leagues_entering_at_this_round varchar, winners_from_previous_round varchar, PRIMARY KEY (leagues_entering_at_this_round))
SQL: select leagues_entering_at_this_round from table_23449363_1 where winners_from_previous_round = "16"