Bill Smugs takes Angry Pixie to a mathematics conference, where people are sitting around different circular tables. Smugs and Pixie too adjust themselves around one circular table. But the Conference could not attract Angry Pixie's attention as she is yawning most of the times. Bill Smugs nudges her, and in reply she tells " Sorry Smugs my brain is hibernating, I need something to get it up ?" To this Bill Smugs asks her "In this conference can you tell me in how many ways n persons can be seated at a circular table if arrangements are considered the same when one can be obtained from the other by rotation?"
