MAT 3120 CRN 49482 - Discrete Mathematics

Purchase College - Fall 2025

Tuesdays & Fridays, 4:30–6:10 PM | NS 3053

Instructor:

Dr. Irina Shablinsky (Irina is fine)
Pronouns: she series
Email: irina.shablinsky@purchase.edu
Office: NS 3002

Office Hours:

Tuesday, Friday 1:00 p.m. – 2:00 p.m. in NS 3002 or remotely.
Walk-ins are welcome. Remote appointments must be scheduled via Starfish.
If these times don’t work for you, email me - we’ll find something that does.

Course Description:

Prerequisites:
Calculus I or higher (grade of C or better)

Covers a variety of topics that provide a foundation for both higher mathematics and computer science. These topics may include logic and formal proofs, set theory, number theory, probability, mathematical induction, algorithms, recurrence relations, equivalence relations and partial orderings, and topics in graph theory (including isomorphism, traversability, planarity, and colorings).

Learning Outcomes

In parentheses below, you can see how the course learning outcomes map to the MATH/CS Program Learning Outcomes.

• Understand structures like sets, functions, relations, equivalence relations, partial orders, trees, and graphs (PLO 1)
• Apply counting principles using the multiplicative property, factorials, and binomial coefficients (PLO 1, 2)
• Analyze and construct rigorous arguments using logic (PLO 1, 3)
• Convert between numerical bases (PLO 1, 2)
• Use proof techniques such as induction, contradiction, and direct proof (PLO 3, 5)
• Typeset mathematical documents using LaTeX (PLO 3)

Required Textbooks

We will be using two free online textbooks this semester:

• Discrete Mathematics: An Open Introduction, 4th Edition (Oscar Levin)
• Combinatorics Through Guided Discovery (Kenneth Bogart)

Lecture notes will be posted on GitHub.

Required Software

You’ll be using LaTeX to typeset homework. You may either:

• Create a free account at Overleaf, or
• Install a LaTeX distribution on your computer.
  Instructions will be given in class.

Attendance

Life happens. If you miss class, check GitHub for notes and turn in any due work. Stay caught up by coming to office hours or working with classmates. Missing a class does not grant you an automatic extension on homework submission.

Late Homework Policy

Mathematics builds on itself, so it’s important to stay on track. If emergencies or illness cause delays, reach out—we can discuss options. Otherwise, late work may not receive feedback or credit if it’s too delayed.

Collaboration Policy/Academic Integrity

Discussing homework is encouraged - copying is not. All submitted work must be your own. Plagiarizing another student’s work can lead to academic sanctions per the Purchase College’s Academic Integrity Policy.

We take cheating seriously!

Policy on ChatGPT and Large Language Models (LLMs)

The use of ChatGPT and other large language models is not allowed for writing or coding assignments in this course, unless you receive explicit permission from me in advance.

This class is about learning the material by engaging with it directly - struggling, questioning, and building understanding step by step. Letting an AI generate your work short-circuits that learning process. Moreover, these tools often produce incorrect or misleading content.

Permitted Uses: Exploratory Investigation. You may use LLMs like ChatGPT to explore broader questions, investigate ideas, or find sources—just not to generate or write your actual assignments. For example, questions like “How is combinatorics used in cryptography or security?” or “What are some visual ways to understand modular arithmetic?” are curiosity-driven and meant to spark learning and discovery, not solve assigned problems for you.

If you're unsure whether something is allowed, just ask me—I'm happy to help clarify.

Violations of this policy will be treated as academic dishonesty and plagiarism, in accordance with Purchase College’s Academic Integrity Policy.

Accessibility Statement

It is my goal that this class be an accessible and welcoming experience for all students, including those with disabilities. You are welcome to talk to me at any point in the semester about course design concerns, but it is always best if we can talk as soon as possible about the need for any modifications. The Office of Disability Resources collaborates directly with students who identify documented disabilities to create accommodation plans, including testing accommodations, for students to access course content and validly demonstrate learning. For those students who may require accommodations, please call or email the Office of Disability Resources, (914) 251-6035, odr@purchase.edu.

Mental Health and Well-Being

Your well-being matters. Check out the Counseling and Behavioral Health website for resources, including emergency contacts and remote counseling

Tutoring

Tutoring is available in Einstein Corner located in the Natural Science Building, room 3046. Students can make appointments via the Starfish platform.More information here.

Cell Phone Policy During the Class

As a courtesy to all, please silence all your devices. No beeping/ringing/vibrating please.

Grading Policy

• 15%: Problem Sets (5-7 problem sets)
• 10%: Departure Pass
• 30% (15%x2): Mid-semester Exams
• 15%: Final Exam
• 10%: Problem Presentations (in-class)
• 20%: Final Project (10% Presentation+10% Paper)

Tentative Class Schedule

A Note About Changes

This syllabus is a guide, not a contract. I may revise the schedule or grading breakdown if needed. The latest version will always be on GitHub, and I’ll keep you posted.