Math 113 (S01): Discrete Structures, Spring 2020
MWF 11-11:50am in Physics 240A (and via zoom starting March 15 [see email or Slack for link])
Office Hours: Schedule appointments here or email me for additional times
Problem session: TTh 7-8pm in Lib 389 (and via zoom starting March 31 [see email or Slack for link])
Drop-in tutoring: SuMTWTh 7-9pm in Lib 204 (and via Google Meet starting March 15)
Text: Discrete Mathematics: Elementary and Beyond (link requires Reed login)
Syllabus | Course log
Challenge problems! Class total: ★★★★★|★★☆★★
Week 1: January 27 - January 31
- M: Welcome and warmup.
- W: Syllabus, §1.1. RQ.
- F: §1.2. RQ.
- Video of the week.
Week 2: February 3 - February 7
Week 3: February 10 - February 14
- M: Equivalence relations. RQ, HW3M due.
- W: §§1.7, 1.8. RQ, HW3W due.
- F: §3.1. RQ, HW3F due.
- Video of the week.
Week 4: February 17 - February 21
- M: No reading. In-class exam covering Chapter 1. One two-sided sheet of notes allowed; no other resources. Review sheet. HW4M due.
- W: §§3.5, 3.6 (ignore the proof of equation (3.5) if you have not seen induction before). RQ, HW4W due.
- F: §2.1. RQ, no homework.
- Video of the week.
Week 5: February 24 - February 28
- M: §2.3. RQ, HW5M due.
- W: §2.4. RQ, HW5W and Exam 1 Revisions due.
- F: Derangements and subfactorials. RQ, HW5F due.
- Video of the week.
Week 6: March 2 - March 6
- M: §4.1. RQ, HW6M due.
- W: §4.2. RQ, HW6W due.
- F: §4.3. RQ, Fibonacci via generating functions, HW6F due.
- Video of the week.
Week 7: March 9 - March 13
Week 8: March 16 - March 20
Class now meeting via zoom.
Instructions for setting up zoom on your computer, tablet, or phone are available via the "Getting Started" links here. (Do this before our first meeting! 🤓)
Homework submission is now via gradescope. You should have received an email saying you were added to our gradescope page. Please contact me if this is not the case or you have trouble with submissions.
- M: §§24-25 (Days 21-22) of the Course Log. RQ, slides, group problems, Catalan bijections handout, HW8M due (DEADLINE EXTENDED TO MARCH 30).
- W:
Joyal's proof of Cayley's formula. RQ, HW8W due (DEADLINE EXTENDED TO MARCH 30).Class cancelled. - F: Class Cancelled. See this page (especially the "Communications to the Community" sidebar) for the latest info on Reed's response to the novel coronavirus pandemic. I will provide information on Math 113's remote meetings and homework submission soon.
- Link of the week. (Richard Stanley's epic problem set on Catalan numbers.)
Spring Break: March 21 - March 29
- Study for Exam 2: two-hour take-home exam with emphasis on Chapters 2, 3, 4, 7, and 8.1-8.2. One two-sided sheet of notes and blank scratch paper allowed, no other resources.
- Fill out this survey by Wednesday, March 25.
Week 9: March 30 - April 3
See March 27 email for updated course procedures!
- M: Joyal's proof of Cayley's formula. RQ, HW8M, HW8W, and HW9M due (via gradescope). Group problems. Exam 2 distributed.
- W: Course log 2.1: Probability spaces. RQ, HW9W due.
- F: Course log 2.3: Independence. RQ, Exam 2 due.
- Video of the week.
- A reframing of the secretary problem.
Week 10: April 6 - April 10
- M: Course log 2.5: Conditional probability. RQ, HW10M due.
- W: Course log 2.7: Expected value. RQ, HW10W due.
- F: Course log 2.9: Bernoulli, binomial, indicator, and geometric random variables. RQ, HW10F due. Group problems and solutions.
- Video of the week.
Week 11: April 13 - April 17
- M: §§6.1-6.3. RQ, HW11M due.
- W: §6.4. RQ, HW11W due. Exam 2 revisions due via email (revise up to two problems and have your scores averaged). Group problems and solutions.
- F: §6.5. No RQ or video, but make sure you read this important section. HW11F due.
- Video of the week.
- Combinatorial necklaces.
Week 12: April 20 - April 24
Week 13: April 27 - May 1
- M: §6.9. RQ, HW13M due. Group problems and solutions.
- W: Read Sunzi's Theorem (pp.51-53 in the Course Log). RQ, HW13W due. Group problems and solutions.
- F: Review session. HW13F due. Final review topics and suggested problems.
- Video of the week.
Final exam
Final review topics and suggested problems.
The final is a 180-minute exam that will be distributed via email at 9am Pacific on Monday, May 11 and is due via gradescope by 11pm Pacific on Wednesday, May 13. During this window, set aside an uninterrupted block of time to take the exam. You are permitted one two-sided sheet of notes and blank scratch paper during the exam, and no other resources. You may write and photograph/scan your work, or you may type your answers on a computer, but all document preparation must take place during the exam period. Email Kyle if you have any questions!
The $\LaTeX$ document preparation system
Poor handwriting? Love escape characters? Too much free time? Try $\LaTeX$!
- $\LaTeX$ at Reed.
- A short guide [pdf] to writing mathematics with $\LaTeX$.
- Change .pdf to .tex in the URL of (nearly) any file accessed from this page to get the $\LaTeX$ source code.
Kyle M. Ormsby