Math 28410 CMSC 27410 -- Honors Combinatorics

CMSC 37200 -- Combinatorics -- Winter 2012


What's new | Course info | Text | Questionnaire | Grading, tests | Policy on collaboration | Puzzles | Exercises, homework | Statistics | prior years

What's new?

To find out what's new, make sure you press your browser's REFRESH button.



Course information

Instructor: László Babai     Ryerson 164     e-mail: laci(at)cs(dot)uchicago(dot)edu.

Course description

Methods of enumeration, proof of existence, explicit construction of discrete structures, the fundamental parameters of such structures (matching number, covering number, chromatic number, independence number of hypergraphs, the Shannon capacity of graphs), combinatorial extrema, regular structures (including finite projective planes), combinatorial duality are discussed. The tools developed include estimation of binomial coefficients, the basic concepts of probability theory over a finite sample space (random variables, independence, expected value, standard deviation, and Chebyshev's and Chernoff's inequalities), linear programming duality and linear relaxation, methods of linear algebra (orthogonality, spectral inequalities), combinatorial applications of A. Weil's character sum estimates.

Mathematical puzzles will pepper the course. The instructor hopes that the course will be fun in many ways.

To get an idea of the breadth and depth of the discussion, check the test problem sets in the "Grading, tests" section.

Prerequisites: The principal prerequisite for this class is a degree of mathematical maturity. Basic linear algebra will be helpful. It helps if you have taken Discrete Mathematics but it is not required.


Go to top

Texts

Your primary text will be your course notes, so make sure you don't miss classes. If you do, you should copy somebody's class notes and discuss the class with them.

There will also be frequent web postings. Please always check this website.

Online texts: instructor's "Discrete Mathematics" lecture notes in PDF (preliminary, incomplete drafts):

Note that the chapter numberings in the two versions are not consistent. Some of the introductory chapters are missing from "advancedDM" while the mini version does not include any of the advanced material; regarding chapters that appear in both versions, the mini version is current.

Printed text:

J. H. van Lint, R. M. Wilson: "A Course in Combinatorics," Cambrdge University Press, ISBN# 0 521 00601 5

Recommended supplementary reading:

J. Matoušek, J. Nešetříl: "Invitation to Discrete Mathematics," by Oxford University Press, ISBN# 098502079.

Recommended background text:

Kenneth H. Rosen: Discrete Mathematics and its Applications (n-th edition, n=2,3,4,5,...)

Recommended reference:

The Discrete Mathematics 2009 course (CMSC37110) is a good source of relevant exercises; check out the homeworks and the tests.

Go to top


Questionnaire

Please send email to the instructor with answers to these questions, even if you are only sitting in on the class, did not register, answered the same questionnaire in an earlier class by the instructor, or have an unusual status. Your answers to these questions will help me better to plan the course. Please write "combinatorics data" in the subject.

Go to top


Course information

Class MWF 11:30 - 12:20 Ry 276

Instructor: László Babai     Ryerson 164     e-mail: laci(at)cs(dot)uchicago(dot)edu.

Office hours: by appointment (please send e-mail)


Grading, tests

Grading is based on homework assigned in class (38%), a midterm (20%), the final exam (38%), and class participation (4%). The tests are closed-book. Proofs discussed in class required; exercises stated in class helpful.

Go to top

Rules on HOMEWORK

Homework will be assigned in class and/or on this website. If you find an error or something that looks suspicious in an assignment, please notify the instructor (by email). If you are the first to point out an error, you may receive bonus points. "DO" problems are meant to check your understanding of the concepts. Do them but do not hand them in. You may encounter them in tests. Challenge problems don't have a specific deadline except they cease to be assigned once they have been discussed in class. If you are working on a challenge problem, please send email to the instructor so as to avoid the problem being discussed before you handed in the solution. Solutions to Challenge problems don't earn you credit toward your grade but they do earn you the instructor's respect, in addition to giving you valuable experience.

Go to top


Policy on collaboration

Studying in groups is strongly encouraged. Collaboration on current homework is discouraged but not prohibited. If you do collaborate, state it at the beginning of your solution (give name of collaborator). DO NOT COPY someone else's solution: after the discussion, throw away any written records. Understand the ideas discussed and give your own rendering. The same applies to other sources such as the Web: give the source (URL), but DO NOT COPY. Understand; then write your own version without looking at the source or your notes.

View the instructor's course material from previous years

Return to the Department of Computer Science home page

Go to top