**Professor Francis Su**

Section 2, Summer 2023

**Meetings:** (zoom) MWF 9am – noon, May 22 – June 23

(except Memorial Day May 29 and Juneteenth Jun 19).

Final Exam due Jun 30.

**Course Webpage**: https://math.hmc.edu/su/math55/

**My Email:** (my last name) at math.hmc.edu

**Grutors: **Sarah Williams, Lea Twicken

**Office Hours**: online (same Zoom link)

Mon-Tue-Wed-Thu-Fri 4pm.

Tue-Thu 11am.

Tue/Thu at 4pm will be hosted by Prof. Su, others hosted by Lea Twicken.

## Course Description

This course is an introduction to combinatorics, number theory, and graph theory with an emphasis on creative problem solving and learning to read and write rigorous proofs. Topics include: combinations, permutations, inclusion-exclusion, strong induction, recurrences, Bayes’ theorem, the Euclidean algorithm, unique factorization, modular arithmetic, Euler’s theorem, RSA encryption, planar and Eulerian graphs, and graph coloring. My goal is to create an inclusive classroom climate where everyone feels responsible for the participation and the joy that others experience in learning.

## Text

There is no required textbook to buy.

We will use portions of Oscar Levin’s *Discrete Mathematics: An Open Introduction* (3rd edition), which is available both as a pdf and in an interactive online ebook.

## Coursework

Homeworks will be assigned and due each class day at 9am via Gradescope. There will be one midterm (due Jun 9) and one final exam (due Jun 30). Each component (homework, midterm, final) is worth at least 30% of your final grade, with the “best” component worth 40%.

Every assignment has an automatic 24 hour extension–you do not need to formally request this extension. Since this is a summer course, I cannot accommodate homeworks later than this unless you are excused by the Dean.

The learning you are doing in this class takes place in a larger framework of school and life. Even if I am excited about teaching and you are excited about learning, work is not the most important thing, and sometimes life can take precedence.

Similarly, ‘success’ by whatever measure is not the most important thing in this course either. Every assessment of your work in this class is a measure of progress, not a measure of promise. Joy, wonder, productive struggle, having your mind expanded—these are more important!

## Honor Code

The HMC Honor Code applies in all matters of conduct concerning this course. Though cooperation on homework assignments is encouraged, you are expected to write up all your solutions individually to ensure your own understanding. Your solutions should acknowledge the assistance of other people or resources of any kind.

A note about online resources: these can sometimes be helpful for learning, but an over-reliance on them can be detrimental to your learning if the ideas do not “pass through your brain”.

Moreover you should not directly use online resources or other people to find solutions to assigned work in this class. Doing so will be regarded as a violation of the HMC honor code. In addition you will miss the joy of discovering a solution for yourself, which is one of the best feelings in the world.

## Lecture Notes and Zoom

I will not be recording lectures, but lecture notes will be available.

## Homeworks

Due on Gradescope each class day **at 9am**.

Some of you may find LaTeX helpful in typesetting your homework. If so, there is a LaTeX class for homework here.