user: Question: How many different values of clubs involved were there when the league entering at this round was Allsvenskan?
Columns: ['Round', 'Clubs remaining', 'Clubs involved', 'Winners from previous round', 'New entries this round', 'Leagues entering at this round']
Types: ['text', 'real', 'real', 'real', 'text', 'text']
Sample row: ['Round 2', 48.0, 32.0, 24.0, '8', 'Superettan (8 teams)']
SQL:

assistant: SELECT COUNT("Clubs involved") FROM "Table" WHERE "Leagues entering at this round" = 'Allsvenskan';