Lesson summary: By the end of this lesson, one should be familiar with the terminology sequence which is just a list of ordered numbers, and the numbers are known as terms. Furthermore, a sequence can be finite (ends) or infinite (continuous). Furthermore, the domain is the relative position of each term (usually starting at one) and the range is the actual number of the term. A series is the indicated sum of all the terms in a sequence and can be modeled using sigma notation. Furthermore, there are two types of equations explicit and recursive. Explicit formulas give the specified term a sub n based on its term number n. Recursive formulas five the specified term a sub n based on its previous term a sub n-1.