Math V3020: Number Theory and Cryptography

**Instructor**: David Hansen

**Office**: 516 Math

**Office Hours**: M 4-6, T 2:30-4

**Email**: lastname @ math.columbia.edu

**Practice Midterm 1 with solutions**

**Practice Midterm 2 with solutions**

**Practice problems for final, batch 1**

**Practice problems for final, batch 1, with solutions**

Homework

**Homework 1** (due 1/24)

**Homework 2** (due 1/31)

**Homework 3** (due 2/7)

**Homework 4** (due 2/14)

**Homework 5** (due 2/28)

**Homework 6** (due 3/21)

**Homework 7** (due 4/23)

Other resources

Some useful Wikipedia articles:

Proof by contradiction

Mathematical induction

Modular arithmetic