Interactive pages for Combinatorics

Subsets	Proposition 1.8
Ordered and unordered combinations	Problem 1.15
The National Lottery	Problem 1.16
The binomial expansion	Example 1.17
Pascal's triangle
Pascal's identity	Proposition 1.19
Complements	Proposition 1.20
Grid routes	Problem 2.7
Counting solutions to some equations	Remark 2.8
An extension of Pascal's identity	Proposition 2.9
Sum of numbers in a triangle	Proposition 2.10
Counting subtriangles	Example 2.11
Lines across circles	Proposition 2.14
Covering a chess board with dominos	Problem 3.3
Tetris	Problem 3.4
The seven bridges of Königsberg	Problem 3.5
Numbers of hairs	Problem 4.3
Handshaking	Proposition 4.4
Sums of subsets	Problem 4.5
Modular sums	Problem 4.7
Piggy bank	Problem 4.8
Tennis and squash	Problem 5.1
Tennis, squash and badminton	Problem 5.2
Derangements of 1234	Proposition 5.11
Derangements of 12345	Proposition 5.11
Numbers coprime with 42	Problem 5.12
Matching problems	Example 6.6

Basic rook problems	Problem 7.1, Ex 7.7, Ex 7.8
Rooks and permutations	Proposition 7.10
Rook polynomial for the full board	Proposition 7.11
Rooks and derangements	Problem 7.13
Snap	Problem 7.15
Problème des ménages	Problem 7.16
Blocking and stripping	Theorem 8.1
Factoring rook polynomials	Example 8.5
Extending a latin rectangle	Problem 8.6
Solving the Problème des ménages	Example 9.1
Solving the Snap problem with Python	Example 10.12
Counting the sets $S_X$	Lemma 10.5
Staircase	Proposition 10.10
The Rugby World Cup
A consistent tournament	Example 13.5
Odd modular tournament	Example 13.12
World Super-Dodgy Wrestling League
Medals
The medal ceremony allocation problem
A big Latin square
Latin square for the dihedral group $D_8$	Example 14.6
Latin square for addition mod $10$	Example 14.7
Extending another latin rectangle	Example 14.22
Orthogonal latin squares	Definition 14.24
Reduced latin squares of size $4$	Proposition 14.31
Affine plane design over $\mathbb{Z}/3$	Example 15.3
Quadratic residue design over $\mathbb{Z}/7$	Example 15.8