# 2: Combinatorics

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Enumerative combinatorics

Date back to the first prehistorics
Who counted; relations
Like sets' permutations
To them were part cult, part folklorics

Michael Toalster, The Omnificent English Dictionary in Limerick Form

Throughout this book we will be counting things. In this chapter we will outline some of the tools that will help us count.

Counting occurs not only in highly sophisticated applications of mathematics to engineering and computer science but also in many basic applications. Like many other powerful and useful tools in mathematics, the concepts are simple; we only have to recognize when and how they can be applied.

This page titled 2: Combinatorics is shared under a CC BY-NC-SA 3.0 license and was authored, remixed, and/or curated by Al Doerr & Ken Levasseur via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.