Math courses are factored into your science gpa. BCPM gpa stands for biology, chemistry, physics, and math. I'm almost sure that computer science classes don't get factored into it.
Your science GPA is also called the "BCPM" GPA by AMCAS because it is calculated based on "Biology, Chemistry, Physics, Math" courses. Computer Science does not count towards this GPA. However, my premed advisor here at school said that your CS GPA might be counted by adcoms as being in your science GPA somehow. I'm not sure if this is true or not?