Combinatorics Through Guided Discovery, 2004a

xii
Discovery had been placed on the aim list of approved open source textbooks, but
there had been no success in finding someone to take on the task of updating the
source to match the pdf. The three of us came together again in May 2017 at the
University of Puget Sound for another workshop on open educational resources
and agreed to cooperate to complete the conversion of this book to PreTeXt. The
fact that ol wanted to use parts of the book for his Fall 2017 class gave us the
motivation required to complete the project over the summer.
For this edition, our goal has been to reproduce the text of Bogart’s final pdf
as faithfullly as possible. Based on our own classroom uses, we have notes about
problems that could use revising, but we agreed the right first step would be to
have source files that matched what Bogart left. We have, however, corrected
obvious errors along the way, which included moving the Supplementary Chapter
Problems in Chapter 3 from the level of a subsection to the level of a section for
consistency with the other chapters. Footnotes may be numbered differently, as in
this edition, a footnote in the body of a problem is rendered with the problem and
numbered in a different sequence. The hints that previously were accessed by links
from the pdf to a Dartmouth webpage have also been included in the backmatter
of the print edition as Appendix D. Links to open hints in place are available in
the HTML version, while in the print and PDF edition, the existence of a hint is
indicated by “(h)” at the end of the problem (or part of a problem). David Farmer
provided invaluable assistance by automating the initial conversion of L A TEX files
to PreTeXt and extracting the text of the hints from the pdf files. We then worked
in parallel to compare the official pdf to what we were able to produce from the
source until they matched. Since this process could not be truly automated, we
suspect there will be some places where Bogart’s pdf and this edition do not match.
We welcome reports of these through issues and pull requests on the Github
site for the book https://github.com/OpenDiscreteMath/ibl-combinatorics/. Going
forward, we would like to see community-driven updates to further develop the
text, either by improving existing problems, adding new problems on existing
topics, or adding new topics suitable for a course based on this text. One area of
development may be to include SageMath to the text, since PreTeXt includles a
number of nice features for doing this and some of the material may benefit from
the addition of a computer algebra system to allow more interesting calculations
than would be feasible by hand.
An html version of this text is available at http://bogart.openmathbooks.org/. A
low-cost print edition is available for purchase online. The cost of the print edition
is kept as low as possible, and any royalties received support costs associated with
hosting and distributing the text. A pdf copy of print edition is also posted on the
book’s site. The pdf may provide a better experience for searching than the HTML
version.
Mitchel T. Keller, Oscar Levin, and Kent E. Morrison
Lexington, Virginia; Greeley, Colorado; and San Jose, California
December 2017