Chapter 5 - Number Theory and the Real Number System - 5.2 The Integers; Order of Operations - Concept and Vocabulary Check - Page 269: 1

$\color{blue}{\left\{..., -3, -2, -1, 0, 1, 2, 3, ...\right\}}$

The set $\left\{..., -3, -2, -1, 0, 1, 2, 3, ...\right\}$ is known as the set of integers. Thus, the missing expression in the given statement is: $\color{blue}{\left\{..., -3, -2, -1, 0, 1, 2, 3, ...\right\}}$