Overview
In set theory and its applications to logic, mathematics, and computer science, set-builder notation is a mathematical notation for describing a set by enumerating its elements, or stating the properties that its members must satisfy.
Defining sets by properties is also known as set comprehension, set abstraction or as defining a set's intension.
Sets defined by enumeration
A set can be described directly by enumerating all of its elements between curly brackets, as in the following two examples:
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