**Spring 2015**

**Homework**

The latest homework will always appear on top.

Homework **9** (the last homework is due on Friday April 24, 2015. It consists of the the following exercises:

54.1, 54.2, 54.3, 54.4, 54.8.

55.1, 55.2, 55.5, 55.7.

56.1, 56.5.

**Suggested extra work**:

After 54.4, think about the width of the poset defined in 54.3 for any n (Hint: Consider n even and n odd separately).

54.9 is a very good exercise to get more practice with posets.

56.7 is "alphabetical" ordering in disguise (this ordering has the more technical name of "lexicographic ordering").

Solutions.

Homework **8** is due on April 15, 2015. It consists of cardinality problems

Homework 8

Homework 8 Solutions.

Homework **7** is due on April 3, 2015:

25.6, 25.9, 25.16, 25.18,

26.7, 26.9, 26.10.

Also do 26.1 to practice.

Solutions.

Homework **6** is due on Wednesday March 26, 2014:

24.1, 24.2, 24.5, 24.6, 24.8, 24.14, 24.16, 24.17, 24.20.

Solutions.

Homework **5** is due on Wednesday March 18, 2015:

22.16, 22.17

20.4, 20.5, 20.9, 20.10, 20.13.

21.3, 21.7, 21.9.

Solutions.

Homework **4** is due on Wednesday February 25, 2014 (well the quiz for it will be then):

Read Sections 17 and 22.

17.3, 17.4, 17.5, 17.8, 17.11, 17.16, 17.21, 17.37.

22.4, 22.5, 22.6, 22.7.

Solutions.

Homework **3** is due on Monday February 16, 2015 (well the quiz for it will be then):

Read Sections 14, 15 and 16.

14.1, 14.3 (no need to prove here), 14.5, 14.6, 14.10, 14.17 (proofs required in 14.6 and 14.10).

15.1, 15.3 (no proof required here), 15.7, 15.8, 15.14, 15.15.

16.1, 16.10, 16.15.

Solutions.

Homework **2** consists of the following exercises. A quiz selecting 2 or 3 of these exercises will be given on Wednesday February 4, 2015:

8.2, 8.4, 8.8, 8.10, 8.15.

9.2, 9.5, 9.7, 9.9, 9.11.

10.1, 10.4, 10.9, 10.12, 10.13.

11.1, 11.2, 11.4, 11.7.

12.1, 12.5, 12.9, 12.12, 12.21, 12.24, 12.30.

Homework 2 Solutions.

Solutions to 10.12 and 10.13.

Homework **1** consists of the following exercises. A quiz selecting 2 or 3 of these exercises will be given on Monday January 26, 2015:

3.1, 3.4, 3.5, 3.7, 3.12, 3.13

4.1, 4.2 and 4.7.

5.1, 5.7, 5.11, 5.18, 5.23

6.1, 6.3, 6.6, 6.9 and 6.13.

7.1, 7.6, 7.10, 7.11, 7.13, 7.17.

Homework 1 Solutions.