 MacMahon's master theorem

MacMahon's Master Theorem is a mathematical tool used in the analysis of combinatorial structures, particularly in the enumeration of various combinatorial objects. While it's not as widely known as some other results in combinatorics, it provides a framework for counting partitions, arrangements, and related structures using generating functions. The theorem is named after the British mathematician Percy MacMahon, who made significant contributions to the theory of partitions and generating functions.