Math 485 is an introductory course on graph theory. I taught it in
Fall 2009. The textbook was West, *Introduction to Graph Theory*,
Second Edition. Here are some course materials.

- Initial Handout: DVI, PS, PDF.
- Homework #1: Section 1.1, pages 14-18, Exercises 12, 13, 14, 20, 22, 25, 26. Due Wednesday, September 9.
- Solutions to Homework #1: DVI, PS, PDF.
- Homework #2: Section 1.2, pages 31-34, Exercises 8, 20, 21, 30. Section 1.3, pages 47-53, Exercises 21, 24, 26. Section 1.4, pages 63-66, Exercises 11, 14, 18, 22, 27. Due Monday, October 5.
- Solutions to Homework #2: DVI, PS, PDF.
- Homework #3: Section 2.1, pages 75-80, Exercises 29, 35, 37.
Section 2.2, pages 92-95, Exercise 18. Section 2.3, pages 103-106,
Exercises 8, 10, 13, 14, 15. Also, letting $L_n$ be the $n$-ladder,
- Find a recursion formula for $\tau(L_n)$.
- Use your recursion to calculate $\tau(L_n)$ for $n=1,2,\ldots,10$.
- Solve your recursion to get an explicit formula for $\tau(L_n)$.
- Find $\lim_{n\to\infty}\tau(L_{n+1})/\tau(L_n)$.

- Solutions to Homework #3: DVI, PS, PDF.
- Study Guide for Midterm Exam: DVI, PS, PDF.
- Midterm Exam: DVI, PS, PDF.
- Solutions to Midterm Exam: DVI, PS, PDF.
- Homework #4: Section 3.1, pages 118-123, Exercises 8, 19, 24, 25. Section 3.2, pages 134-136, Exercise 6. Section 6.1, pages 243-246 63-66, Exercises 12, 25, 35. Section 6.2, pages 255-256, Exercise 6. Due Friday, December 4.
- Solutions to Homework #4: DVI, PS, PDF.
- Study Guide for Final Exam: DVI, PS, PDF.
- Final Exam: DVI, PS, PDF.

**FINAL EXAM: Monday, December 14, 8:00 AM, 114 Ag Engr.**

t20@psu.edu / 17 December 2009