5/13/09 Homework 9 solutions are available—see Homework page

4/21/09 New notes: Euler’s Theorem & Cycle Lemma—see Notes page

4/21/09 Exam 2 was Friday, April 17—see Exams page

5/4/09 Homework 9 due Monday, May 11—see Homework page

It will not be possible to accept for grading any papers after class that day.

As an extra incentive for doing this last homework set, your total score on the 5 problems will be divided by 40 to give your score on the set. In other words, you may earn up to 25% extra credit on this assignment.

4/27/09 Homework 8 due Monday, May 4—see Homework page

It will not be possible to accept for grading any papers after class that day.

5/3/09 More credit for Homework 7 #3?

If you misread #3 of Homework 7 to mean that you should give the total number of walks of length k between all possible pairs of adjacent vertices— rather than, as intended, the number of such walks for an arbitrary such pair—so as to get answers that were 9 times the answers I obtained for each k, then you deserve full credit. Show me your paper!

4/18/09 Problem Set 7 posted; due Monday, April 27—see Homework page

4/4/09 A proof of Fermat’s Little Theorem is available—see Notes page

4/5/09 Homework Set 6 due Monday, April 13—see Homework page

A corrected version was posted April 5. The correction is to the wording and data originally shown in #5; that data was available in Set6#5.nb.That notebook has been corrected, too.

As stated you may either work in a team on this set or else do it individually (ypur choice).

4/3/09 Homework Set 5 due date postponed to Wednesday, April 4—see Homework page

3/22/09 Homework Set 4 due Monday, March 30—see Homework page

The due date previously listed (March 23) was in error!

3/13/09 New notebooks available—see Files page

New notebooks include: Divisibility.nb and Primes.nb, on number theory; and Factorial.nb and Fibonacci.nb, on recursive definitions, among other things.

(Fibonacci.nb is RecursiveFunctions.nb renamed.)

3/9/09 Exam 1 solutions are available—see Exams page

2/27/09 Course packet text reprints ready at Textbook Annex

At long last, the Textbook Annex has ready the correct version of the textbook—the version where page 22 begins with Review Exercise 1.8.8. This is in the form of a Course Pack reprint.

If you did not yet get the textbook, please get one of these Course Pack copies now. It’s free!

If you previously got one of the temporary “proxy” copies with just Chapters 1–5, please return your temporary copy to the Textbook Annex for a refund! Pick up then the new Course Pack.

We’re going to be beyond Chapter 5 in a few days!

2/26/09 Revised version of Finite Sets notes available—see Notes page

The revised version now includes in Section 6 a new subsection on the Generalized Pigeonhole Principle and corrects terminology in Section 7 involving the “blocks” of a partition.

3/8/09 Exam 1 Monday, March 9 (during class time)

In case of a snow emergency closing that cancels class March 9, the exam will be Wedesday, March 11.

Different sets of Math 455 students will be taking Exam 1 in different rooms. These  people take the exam in the Math & Stat Resource Center, LGRT 110:

Burgholzer               Murphy
Calabrese                Mwangi
Crowley                   Ornellas
Ding                         Provost
Heimann                  Rand
Hydefrost                Shields
Kalinowski              Silvia
Lau                          Zhang

Everybody else will take the exam in ELAB 307. (For there, be sure your ECS account works!)

3/2/09 Homework 3 not postponed at all, still due Wednesday in class

There is nothing I would have done in class today — and will do, instead, Wednesday — that was not already covered in class or in the readings and that would be of direct relevance to any of the homework problems.  (In fact, what I would have done today is introduce yet two more methods of counting in certain situations; in a way this might make things more confusing, not less, for the homework set in hand, since so far as I am aware these two new methods are not applicable to any of the problems!)

Moreover, it would be unwise to extend the due date because then you'd not get the papers back in time to have for studying for the exam the week of March 9….

2/24/09 Homework set 3 due Wednesday, March 4—see Homework page

Note that this set is to be done individually, not in a team.

2/17/09 Homework set 2 due Monday, Feb. 23—see Homework page

I revised and reposted the assignment so that, for the problems taken from the textbook, the entire problem is quoted directly. This is to avoid any confusion as to which problem is intended, as we try to disentangle the confusing situation of two slightly different versions of the textbook already in your hands.

2/8/09 Regular class resumes in LGRT 219 Monday, February 9

2/4/09 Homework set 1 due Friday, Feb. 13—see Homework page

02/03/09 Class meets in ELAB 307 Wednesday & Friday, Feb. 4 & 6

Be sure you can access your OIT UDrive (http://udrive.oit.umass.edu/) for saving files.

Here’s a map showing where ELAB is:

01/7/09 Welcome to my Math 455 for Spring 2009

Math 455 is an introduction to some topics in pure mathematics that underlie areas in computer science and computing engineering, including induction and recursion; elementary number theory including application to public-key cryptography; combinatorics (systematic counting); and graph theory.

Details about course organization and requirements appear on the various pages on the About section of this web site and are summarized here.

Briefly: There will be two mid-semester exams, a final exam, and frequent homework that will include computer work. You will be introduced to the software package Mathematica and will use it both as a computing tool and as a medium in which to express mathematical ideas.

01/7/09 Required textbook and software—see also Text and Software pages

Copies of the textbook are not expected to arrive at the Textbook Annex until February. However, buy the text there now! You will get for now a packet of reprints the first several chapters; when the actual books arrive, take back the reprint packet and exchange it for the book. (You must turn back the reprint packet to get the book, as the publisher requires this.)

Mathematica version 6.0.3 (or later) software package will be used; version 7 is preferred. Mathematica is installed at OIT and some other UMass public labs. Iif you want to install it on on your own computer, you may buy an inexpensive, limited-term student license—see the Software page.

Last modified: 05/24/09