Enumerative Combinatorics

• Factorial
• Binomial, multinomial coefficients
• Stirling numbers of the first and second kind
• Fibonacci numbers, Bernoulli numbers, Harmonic numbers, and Eulerian numbers
• Number of partitions of n
• Enumeration of restricted and unrestricted partitions
• Sets of subsets, multisets, and subsequences of sets
• Permutations of sets (as sequences)