CSCI 0220

Discrete Structures and Probability

CSCI 0220 meets Mondays, Wednesdays, and Fridays from 2:00 - 2:50 pm.

I don't know about you, but we're feeling 22! This class, offered both semesters at Brown University, gives you the tools to explore interesting questions and convince yourself and others of their answers. You'll be introduced to new worlds of ideas and ways of thinking. We'll learn about Logic, Set Theory, Number Theory, Combinatorics, and Probability. If these topics sound unfamiliar, not to fear—you're in exactly the right place! This course assumes no prior experience with these topics.

Important info before the semester starts:

  • Exams are in-person, and there will be a total of 3 in-class (non-final) exams and one final exam.
  • Lectures will be streamed and recorded; attendance is strongly encouraged.
  • Attendance at weekly recitation sections is required.

For the Spring 2026 semester, this class will be taught by professor Robert Lewis. If needed, you can contact him at robert_lewis@brown.edu.

Everything Bagel

Assignments

Assignments Photo
Homework Template Released Due Solutions
HW0 - Jan 21 Jan 28 -
HW1 Overleaf Template Jan 29 Feb 4 -
HW2 - Feb 5 Feb 11 -
HW3 - Feb 12 Feb 20 -
HW4 - Feb 19 Feb 25 -
HW5 - Feb 26 Mar 6 -
HW6 - Mar 5 Mar 11 -
HW7 - Mar 12 Mar 18 -
HW8 - Mar 19 Apr 3 -
HW9 - Apr 9 Apr 15 -
HW10 - Apr 16 Apr 24 -
Recitation Template Released Solution
Recitation 1 Overleaf Template Jan 27 -
Recitation 2 - Feb 5 -
Recitation 3 - Feb 12 -
Recitation 4 - Feb 19 -
Recitation 5 - Feb 26 -
Recitation 6 - Mar 5 -
Recitation 7 - Mar 12 -
Recitation 8 - Apr 2 -
Recitation 9 - Apr 9 -
Recitation 10 - Apr 16 -

Lectures

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Lecture Date Topic Recording
1 Jan 21 Intro Video
2 Jan 23 Statements, Proofs, and Contradictions Video
3 Jan 26 Language of Propositional Logic Video
4 Jan 28 Formal Proofs in Propositional Logic Video
5 Jan 30 Propositional Proofs and Validity Video
6 Feb 2 Language of First Order Logic Video
7 Feb 4 Formal Proofs in First Order Logic Video
8 Feb 6 Language of Set Theory Video
9 Feb 9 Proof about Sets Video
10 Feb 11 Binary Relations Video
11 Feb 13 Injectivity, Surjectivity, Bijectivity Video
- Feb 16 Long Weekend - NO CLASS -
12 Feb 18 More Properties of Relations Video
13 Feb 20 Induction Video
14 Feb 23 Variants of Induction Video
15 Feb 25 Number Theory -- Division Video
16 Feb 27 Division Algorithm Video
- Mar 2 EXAM 1 (Logic & Set Theory) -
17 Mar 4 Modular Arithmetic Video
18 Mar 6 Multiplicative Inverses Video
19 Mar 9 Number Theory in Lean Video
20 Mar 11 Message Passing, RSA Video
21 Mar 13 Encryption and Ethics Video
22 Mar 16 Intro to Counting Video
23 Mar 18 Division Rule Video
24 Mar 20 Binomial Theorem, Inclusion-Exclusion Video
- Mar 23 Spring Recess - NO CLASS -
- Mar 25 Spring Recess - NO CLASS -
- Mar 27 Spring Recess - NO CLASS -
25 Mar 30 Pigeonhole Principle Video
26 Apr 1 Counting Trees Video
27 Apr 3 Intro to Probability Video
28 Apr 6 Probability and Independence Video
- Apr 8 EXAM 2 (Number Theory & Combinatorics) -
29 Apr 10 Random Variables, Expectation Video
30 Apr 13 Conditional Expectation Video
31 Apr 15 Linearity of Expectation Video
32 Apr 17 Bayes' Rule Video
33 Apr 20 Induction and Proofs on Data Video
- Apr 22 EXAM 3 (Probability + Redo 1) -

Calendar

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Resources

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Staff

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Instructors

Robert Y. Lewis

Head TAs

Ilija Ivanov
Amy Qiao
Alyssa Sun

UTA-STAs

Zach Quitkin

UTAs

Nathan Phan
John Rathgeber
Lukas Strelecky
Grace Wang
Moses Yang