Durant and Westbrook are playing a three-point challenge game to improve long distance shooting. Each time each of them makes a basket, 3 points are added to their respective scores. Durant has 18 points and Westbrook has 12 points. Which of the following options has the pair of explicit formulas that represents the number of points for each player as an arithmetic sequence?

Durant: 18+(n-1)(3) Westbrook: 12+(n-1)(3)
Durant: 18-(n-1)(3) Westbrook: 12-(n-1)(3)
Durant: 18+(n-3) Westbrook: 12+(n-3)
Durant: 18+3n Westbrook: 12+3n