Three is the only prime which is one less than a perfect square. Any other number which is 
  
    
      
        
          n
          
            2
          
        
      
    
    {\displaystyle n^{2}}
   − 1 for some integer 
  
    
      
        n
      
    
    {\displaystyle n}
   is not prime, since it is (
  
    
      
        n
      
    
    {\displaystyle n}
   − 1)(
  
    
      
        n
      
    
    {\displaystyle n}
   + 1).
In cricket, a bowler who is credited with dismissals of batsmen on three consecutive deliveries has achieved a "hat-trick". In Gaelic games (Gaelic football for men and women, hurling, and camogie), three points are awarded for a goal, scored when the ball passes underneath the crossbar and between the goal posts. In ice hockey:
Scoring three goals is called a "hat trick" (usually not hyphenated in North America). A team will typically have three forwards on the ice at any given time. In professional wrestling, a pin is when one holds the opponents shoulders against the mat for a count of three. In rugby union:
A successful penalty kick for goal or drop goal is worth three points. In the French variation of the bonus points system, a team receives a bonus point in the league standings if it wins a match while scoring at least three more tries than its opponent. The starting tighthead prop wears the jersey number 3. In rugby league:
One of the two starting centres wears the jersey number 3. (An exception to this rule is the Super League, which uses static squad numbering.) A "threepeat" is a term for winning three consecutive championships. A triathlon consists of three events: swimming, bicycling, and running. In many sports a competitor or team is said to win a Triple Crown if they win three particularly prestigious competitions.