Students will learn what an arithmetic series is, how to determine whether a sequence is arithmetic, and how to extend a sequence which is known to be arithmetic. Students should see at least one example of an arithmetic sequence, such as $$-5, -3, -1, 1, \ldots$$

and at least one non-example of an arithmetic sequence, such as

$$1, 3, 6, 10, \ldots$$And here's a problem involving the extension of an arithmetic sequence:

$$-8,\ -14,\ -20,\ -26,\ \underline{\hspace{12mm}}, \ldots$$