MATH 240 - DISCRETE STRUCTURES I.  Fall 2011


Tentative schedule


Week 1:

Wednesday, September 5th Introduction. Sets: Venn diagrams; set identities.

Friday, September 7th Logic: propositional calculus; logical operators.

Week 2
:

Reading: Notes on logic by Jacques Verstraete are posted here. Also compare with Rosen.

Monday September 10th
Logic: The conditional and biconditional (equivalence) statements.
Wednesday, September 12th Logic: tautologies and contradictions. Examples of Direct Proofs and Proof by Contradiction. Assignment 1 assigned.
Friday, September 14th Logic: combinatorial circuits; circuit complexity.

Week 3
:


Monday September 17th Asymptotic Bounds. Polynomial and Exponential Time Algorithms.

For more background on the topic of this and the next lecture see these notes (especially Section 5).
Wednesday, September 19th Example: P and NP.
Notes on the definition of NP, by Bruce Shepherd: pages 29-31 of this document.

Friday, September 21st Arrow's impossibility theorem. See these notes.


Week 4
:


Monday September 24th Logic: predicate calculus.
Assignment 1 due.
Wednesday, September 26th Logic: proofs by induction. Assignment 2 assigned.
Friday, September 28th
Number Theory: prime factorisation. (Reading:"Why isn't the fundamental theorem of arithmetic obvious".)

Week 5:


Monday October 1st Number Theory: applications of unique prime factorizations.

Wednesday, October 3rd Number Theory: Greatest common divisiors.

Friday, October 5th Number Theory: Euclid's Algorithm.

Week 6
:


Monday October 8th Thanksgiving. No lecture.
Wednesday, October 10th Number Theory: Modular arithmetic.
Supplemental notes on modular arithmetic, by Jacques Verstraete.
(NOTE: there are two errors in these notes.
In the first example on page 4, the 3 should be 13.
In the second example, the computation has a mistake; the correct answer to 121x=23(mod 501) is 83, not 151.)
Assignment 2 due.
Friday, October 12th Number Theory: Modular arithmetic and prime fields.
.

Week 7
:


Monday, October 15th Number Theory: Modular Equations. 
Wednesday, October 17th Number Theory: Fermat Test, Miller-Rabin Test, Recognizing Primes.

Friday, October 19th Review for midterm.


Week 8:


Monday, October 22th
Midterm.

Wednesday, October 24th Example: cryptography.
Wednesday, October 24th
Example: RSA encryption. (Supplemental material: Brit Cruise on Cryptography.)

Friday, October 26th Combinatorics: functions, counting.

Week 9:


Monday, October 29th Combinatorics: subsets; the Binomial theorem.
Wednesday, October 31st Combinatorics: Pascal's triangle.
Friday, Nov 2nd
Combinatorics: solving recurrence equations.

Week 10
:


Monday, November 5th Combinatorics: inclusion-exclusion.
Wednesday, November 7th Combinatorics: inclusion-exclusion; the derangement problem.
Friday, November 9th Combinatorics: inclusion-exclusion; Euler's function.

Week 11
:


Monday, November 12th. Combinatorics: the Multinomial theorem.
Wednesday, November 14th Graph Theory: the Handshaking lemma. Euler circuits. (Supplemental material: Early writings on graph theory: Euler circuits and the Königsberg bridge problem.)
Friday, November 16th Graph Theory: Hamiltonian cycles.

Week 12
:


Monday, November 19th. Graph Theory: trees.
Wednesday, November 21st Graph Theory: representing spanning trees.
Friday, November 23rd Graph Theory: counting spanning trees.

Week 13
:


Monday November 26th Graph Theory: planar graphs.
Wednesday, November 28th Graph Theory: graph coloring; characterising bipartite graphs.
Friday, November 30th
Graph Theory: the 4-color theorem; the 5-color theorem.
Week 14:

Monday, December 3nd Game Theory

Wednesday, December 5th
Review