1. The Integers
Numbers and Sequences
Diophantine Approximation
Sums and Products
Mathematical Induction
The Fibonacci Numbers
Divisibility
2. Integer Representations and Operations
Representations of Integers
Computer Operations with Integers
Complexity of Integer Operations
3. Greatest Common Divisors
Greatest Common Divisors and Their Properties
The Euclidean Algorithm
Linear Diophantine Equations
4. Prime Numbers
Prime Numbers
The Distribution of Primes
The Fundamental Theorem of Arithmetic
Factorization Methods and the Fermat Numbers
5. Congruences
Introduction to Congruences
Linear Congruences
The Chinese Remainder Theorem
Polynomial Congruences
Systems of Linear Congruences
6. Applications of Congruences
Divisibility Tests
The Perpetual Calendar
Round-Robin Tournaments
Hashing Functions
Check Digits
7. Some Special Congruences
Wilson's Theorem and Fermat's Little Theorem
Pseudoprimes
Euler's Theorem
8. Arithmetic Functions
The Euler Phi-Function
The Sum and Number of Divisors
Perfect Numbers and Mersenne Primes
Möbius Inversion
Partitions
9. Cryptography
Character Ciphers
Block and Stream Ciphers
Exponentiation Ciphers
Public Key Cryptography
Cryptographic Protocols and Applications
10. Primitive Roots
The Order of an Integer and Primitive Roots
Primitive Roots for Primes
The Existence of Primitive Roots
Discrete Logarithms and Index Arithmetic
Primality Tests Using Orders of Integers and Primitive Roots
Universal Exponents
11. Applications of Primitive Roots and the Order of an Integer
Pseudorandom Numbers
The EIGamal Cryptosystem
An Application to the Splicing of Telephone Cables
12. Quadratic Residues
Quadratic Residues and Nonresidues
The Law of Quadratic Reciprocity
The Jacobi Symbol
Euler Pseudoprimes
Zero-Knowledge Proofs
13. Decimal Fractions and Continued Fractions
Decimal Fractions
Finite Continued Fractions
Infinite Continued Fractions
Periodic Continued Fractions
Factoring Using Continued Fractions
14. Nonlinear Diophantine Equations and Elliptic Curves
Pythagorean Triples
Fermat's Last Theorem
Sum of Squares
Pell's Equation
Congruent Numbers and Elliptic Curves
Elliptic Curves Modulo Primes
Applications of Elliptic Curves
15. The Gaussian Integers
Gaussian Integers and Gaussian Primes
Greatest Common Divisors and Unique Factorization
Gaussian Integers and Sums of Squares