CS202: Discrete Structures

4.4: Factorial Notation

• Massachusetts Institute of Technology: Srini Devadas and Eric Lehman's "Sums, Approximations, and Asymptotics II" URL

  Read Section 2 "The Factorial Function." The reading also applies to the Subunit 4.4.1 and Subunit 4.4.2. In reading for Subunit 4.4.2, below, see the binomial theorem and its generalization to the multinomial theorem.

  Note the first ten factorials: 10! 9! 8! 7! 6! 5! 4! 3! 2! 1! = 10₁ x 9₂ x 8₃ x 7₄ x 6₅ x 5₆ x 4₇ x 3₈ x 2₉ x 1₁₀.

• Massachusetts Institute of Technology: Srini Devadas and Eric Lehman's "Counting II" and "Counting III" URL

  In "Counting II", read Section 1.3, "Permutations." In "Counting III", read Section 1.3, "Combinations" and Section 2, "Binomial Theorem."