According to answers.com, the Alamodome's seating capacity for basketball is 20,662 which can be expanded to 39,500.
Alamodome has a seating capacity of 65,000 people for American football, 52,295 people for baseball, 59,000 people for Canadian football, 20,662 people for basketball, 36,000 people for ice hockey, and 40,000 people when used for boxing.
The Verizon Center has a seating capacity of 20,356 for basketball and 18,506 for hockey.
The seating capacity for basketball at the Thomas and Mack Center is 18,776.
Georgia Dome has a seating capacity of 74,228 people for football and 71,000 people for basketball.
Ford Field has a seating capacity of 65,000 people for football and 78,000 people for basketball.
The seating capacity for Madison Square Garden in New York City, will depend on the event. For basketball it has a seating capacity of 19,763. For hockey it is 17,200. The theater capacity is 5,600.
For a basketball game there is 19309 seats
Brigham young university
The Amway Center has a seating capacity of 18,846 for NBA games and 20,000 for NCAA basketball games.