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Chapter1An Introduction to Combinatorics

As we hope you will sense right from the beginning, we believe that combinatorial mathematics is one of the most fascinating and captivating subjects on the planet. Combinatorics is very concrete and has a wide range of applications, but it also has an intellectually appealing theoretical side. Our goal is to give you a taste of both. In order to begin, we want to develop, through a series of examples, a feeling for what types of problems combinatorics addresses.