Over 30 years, whew! I'm very pleased to be able to add this volume to the other three (I've had to replace volumes 1 and 3 because I wore out my first copies). And, I'm very glad I don't have to complete a graduate course that would use this volume as a text, I'm not sure I'd have the stamina to make it though. Thank you, Dr. Knuth, for your guidance and challenges. They certainly made a significant difference in the success of my career. I'm sure that those of you who delve into this volume will be enlightened by it as well. I'm not qualified to technically critique or perhaps even understand a lot of the material in this book, but at least I'll have the rest of my life to try. Now, doesn't he still owe us one more?

Knuth has written many books considered classics. Some of the previous works have been set-up for where the real fun is - Combinatorics. In one of my own columns, I say "Never trust the brute-force power of a computer network to do the job of a combinatorialist." In 1967, John P. Robinson and Arthur J. Bernstein published an optimal Golomb ruler with 24 marks (OGR24). Their solution was confirmed in 2004 Algorithm S: Breadth-first synthesis of BDDs

Page 293 - Balanced and Complementary Gray codes.

Page 424 - Stirling numbers and set partitions.

Page 449 - Generating binary trees

Helpful mathematical illustrations feature prominently throughout the book, and pretty much every page is gorgeously formatted. Knuth developed TeX in part to produce beautiful books, and that is on display here.

Many thoughtful questions are provided as an aid to learning these very useful techniques. The Answers section runs for 303 pages.

It will take me months or years to digest most the information in this work, but I can't imagine a better presentation for this difficult but lucratively useful material.