Fermat's Little Theorem
Discover it and use it.

We will discover a famous theorem about prime numbers that turns up in fractions, circular codes, and powers of integers.  On the way, we'll learn about bar codes, YouTube codes, and codes that correct themselves for errors.  We'll also learn to find cube-roots without paper or calculator.  Then we'll see how the "famous theorem" is used to securely transmit your credit card number and other information over the Internet.

1. Reciprocals of Integers       Problem Set 1   Answers 1

2. Number of Codes                Problem Set 2   Answers 2

3. Error Correction                 Problem Set 3   Answers 3

4. Plate Patterns                      Problem Set 4   Answers 4

5. Calculating m mod n           Problem Set 5   Answers 5

6. Properties of Fifth Powers  Problem Set 6   Answers 6

7. an mod p                             Problem Set 7   Answers 7

8. Public Key Encryption       Problem Set 8   Answers 8