`
Multi-counting
7.1
7.7
Product Rule
Sequences
sets
strings
alphabet
7.6
8.2
7.2
7.4
7.5
r-permutations
Permutation
8.2
Combinations
8.3
Permutations with repetition
8.4
7.9
Sum Rule
mutually disjoint
7.7
Line-ups
8.1
Counting by Complement
7.8
Counting Multisets
8.5
distinguishable items
indistinguishable items