But he does not know the password required for entry. The man observes others being let in, by talking to the nightclub bouncer. The bouncer says "TWELVE," the visitor then says "SIX" and got let in. Another visitor appeared and now the bouncer says "SIX," the visitor then says "THREE" and got let in too. The man now understands the pattern, and he goes up to the entrance. The bouncer says "TEN," and quickly the man says "FIVE."
The man is turned away rudely by the bouncer. Why?