This book develops the theory of partitions. Simply put, the partitions of a number are the ways of writing that number as sums of positive integers. For example, the five partitions of 4 are 4: 3+1, 2+2, 2+1+1, and 1+1+1+1. Surprisingly, such a simple matter requires some deep mathematics for its study. This book considers the many theoretical aspects of this subject, which have in turn recently found applications to statistical mechanics, computer science and other branches of mathematics. With minimal prerequisites, this book is suitable for students as well as researchers in combinatorics, analysis, and number theory.
It took the lucky convergence of the COVID-19 lockdown (with more time than one could ever have imagined) and watching the wonderful movie, The Man who Knew Infinity (as the inspiration) to reread parts of this unique reference book on Partitions. My focus was primarily on chapter 5 (The Hardy-Ramannjan-Rademcher Expansion of p(n)) and 7 (Identities of the Rodgers-Ramannjan Type). Like reading the score of a Bach fugue, I felt awe and no small degree of humility in navigating through the work of these great mathematicians.
Overall, the best reference book on the general topic I have found.