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Statistics
Number Theory
Java
Data Structures
Cornerstones
Calculus
Day
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Use / Do
1
Closure and Sets of Numbers
Remainders and Divisibility
2
Direct Arguments
Proof by Cases
Exercises - Divisibility
3
Indirect Argument (Proof by Contradiction)
Secret Decoder Rings and the Caeser Cipher
Simple Transposition Ciphers
(English) Letter Frequencies
Encryptor / Decryptor
Exercises - Indirect Arguments
Exercises - The Pigeonhole Principle
Read some fictional history...
Crack the related "Strap Code"
4
Summations and Sigma Notation
Two Important Properties of Sums (Linearity)
The Principle of Mathematical Induction
Exercises - Induction and Sums
5
Variations on Induction
Proof of the Division Algorithm
Exercises - Induction in Other Contexts
6
Patterns and Conjectures
Generating Pascal's Triangle
An Odd Question About Pascal's Triangle
Fibonacci's Rabbits
Numbers in Different Bases
A Curious Inequality
Exercises - Patterns and Conjectures
Exercises - The Collatz Conjecture
7
Pythagorean Triples
Exercises - Pythagorean Triples
8
Permutation Puzzles (and Transposition Ciphers Revisited)
Jug Problems
Exercises - Permutation Puzzles
9
The Euclidean Algorithm
Lame's Theorem
Exercises - The Euclidean Algorithm
Gcd Finder
10
Linear Combinations
Exercises - Linear Combinations
Linear Combination Finder
11
Congruence
Solving Linear Congruences
Affine Ciphers
Exercises - Linear Congruences
Get an Encrypted Message
12
Fundamental Theorem of Arithmetic
Exercises - The Fundamental Theorem of Arithmetic
13
Vigenere's Cipher
Vectors
Dot Products, Norms, and Angles Between Vectors
Exercises - Vigenere's Cipher
Vigenere Subsequence Analyzer
Review
14
Linear Transformations
Inverses of Linear Transformations
Exercises - Linear Transformations
15
The Hill Cipher
Exercises - The Hill Cipher
16
Continued Fractions
Exercises - Continued Fractions
17
Wilson's Theorem
Converse of Wilson's Theorem
Exercises - Wilson's Theorem
18
Fast Exponentiation
Fermat's Little Theorem
Exercises - Fast Exponentiation and Fermat's Little Theorem
19
Primality Testing and Carmichael Numbers
Euler's Theorem
Exercises - Primality Testing and Carmichael Numbers
20
Euler's Phi Function
Table of Phi Values (0-224)
Exercises - Euler's Theorem
21
Euler's Phi and the Chinese Remainder Theorem
Solving a System of Congruences
Exercises - Chinese Remainder Theorem
22
Cardinality and Infinite Sets
Enumeration of the (Positive) Rationals
Cantor's Diagonal Argument
Exercises - Cardinality and Infinite Sets
23
The Cardinality of a Power Set
Review
Exercises - Review Exercises (Set B)
24
The Diffie-Hellman Key Exchange Protocol
25
RSA and Public Key Codes
Exercises - RSA and Public Key Codes
26
Finding Phi is Equivalent to Factoring
Finding k
th
Roots (mod n)
27
Finding Square Roots (mod n)
Exercises - Finding Roots
28
Finding Certain Roots is Equivalent to Factoring
29
Flipping Coins over the Telephone
30
The Order of an Integer
Primitive Roots
Index Arithmetic
Exercises - The Order of an Integer and Primitive Roots
Exercises - Index Arithmetic
31
Power Residues and Legendre's Symbol
Properties of Legendre's Symbol
Exercises - Legendre's Symbol
32
Gauss' Lemma
A Consequence of Gauss' Lemma
33
Quadratic Reciprocity
Review
Exercises - Review Exercises (Set C)