The head coach of a basketball team stipulates that, if the No. 1 player is on the court and No. 3 player is also not on the court, then at least one of the No. 5 and No. 7 players must be on the court.
the sufficient condition for the No. 1 player not on the court?
No. 3 player is not on the court, No. 5 and No. 7 players are on the court.