# Errata

## 2017 Edition

### Corrected in the 2017.2 Edition

• Section 5.4.2 (print page 84): The phrase “proving showing” should read “showing”. (Reported by Jephian Lin, National Sun Yat-sen University.)
• Discussion 6.1 (print page 113): In “Alice was intrigued by the critic’s choices and his rankings” , the antecedent of “his” is the critic, not Alice. (Reported by Jephian Lin, National Sun Yat-sen University.)
• Section 6.3.1 (print page 123): In the first paragraph, the expression “$$D(x)$$, $$D[x]$$, $$D(s)$$, and $$D[S]$$” should be “$$D(x)$$, $$D[x]$$, $$D(S)$$, and $$D[S]$$”  and the expression “$$U(x)$$, $$U[x]$$, $$U(s)$$, and $$U[S]$$” should be “$$U(x)$$, $$U[x]$$, $$U(S)$$, and $$U[S]$$”. That is, the two uses of lower case $$s$$ should be upper case. (Reported by Jephian Lin, National Sun Yat-sen University.)

### Corrected in the 2017.1 Edition

• Section 3.3 (print page 43): There is an sentence that says $$r(1)=1$$, but it should say $$r(1)=2$$.
• Section 6.7 (print page 131): Near the very end of the section, there is a sentence that reads “Erase the line joining points $$c$$ and $$d$$.” It should read “Erase the line joining points $$c$$ and $$j$$.” (Reported by Eric Zhu, Georgia Tech.)
• Section 8.2 (print page 165): Change “we must choose $$k-1$$ of them as the locations for dividers” to “we must choose $$n-1$$ of them as the locations for dividers”. Also change $$k-1$$ to $$n-1$$ in the bottom of the first binomial coefficient in the following displayed equation. (Reported by Jie Han, University of Rhode Island.)
• Example 9.10 (print page 192): There is a paragraph here that makes misleading claims about the role of the binomial theorem in allowing the square roots to cancel and give only integer values. (Reported by Csaba Biró, University of Louisville.)

## 2016 Edition

### Corrected in the 2017 Edition

• Section 2.1 (print page 30): In Example 2.32, the string should be MITCHELTKELLERANDWILLIAMTTROTTERAREGENIUSES!! instead of the string given. (Note that the uncorrected string ends in AREREGENIUSES!! with an extra “RE”.) (Reported by Fidel Barrera Cruz, Georgia Tech.)
• Section 6.1: The definition of linear order comes after the idea is first used. The two paragraphs immediately after Figure 6.9 should be moved between Discussion 6.6 and Example 6.7. (Suggested by Fidel Barrera Cruz, Georgia Tech.)
• Section 7.5: Some references in this section were missing the type word “Theorem” or “Proposition”. (Reported by David Farmer.)
• Exercise 7.2: Once you work out how many students know all three languages, only Java and C++, and only Java and Python, you run into a problem because not enough students know Java in order to satisfy this. Change the number of students who know Java from 748 to 792. (Reported via an anonymous Georgia Tech student via Fidel Barrera Cruz.)
• Exercise 8.15.b: This exercise should be done with ordinary generating functions rather than exponential. (Reported by Csaba Biro, University of Louisville.)
• Example 9.25: The expression for $$R(x)$$ in rational form has an extra factor of 2 in the denominator. The correct expression is $$\displaystyle R(x) = \frac{6x^2-5x+2}{(1-2x)(1-x-2x^2)}$$. (The partial fraction expansion given is based on the correct rational form, and the final solution is correct. This was discovered by the authors while adding some SageMathCells to prepare the 2017 edition.)

### Corrected in the 2016.1 Edition

The errors below have been corrected in the 2016.1 Edition, which is the default HTML version. There is no PDF or print version of the 2016.1 Edition. The 2016 Edition HTML version, which matches the PDF and print versions remains available.

• Section 2.2 (print page 20): In the paragraph before Example 2.7, P(26,20) should be P(26,6). (Reported by Rachel Chaiser, University of Puget Sound)
• Section 5.1 (print page 70): The second-to-last sentence of the second paragraph should read “graph is a helpful tool”, not “graph is a helpful too”. (Reported by Ethan Raymond, University of Toronto.)
• Section 7.1 (print page 142): In Example 7.3, there are two consecutive greater than signs in one place. The erroneous text should read “we must exclude any solution in which $$x_3>7$$.” (Reported by Fidel Barrera Cruz, Georgia Tech.)
• Section 8.1 (print page 158): The series for $$\log(1+x)$$ in Example 8.2 is missing a factor of $$(-1)^{n+1}$$. That is, the series should be $$\log(1+x) = \displaystyle\sum_{n=1}^\infty (-1)^{n+1} \frac{x^n}{n}$$, and the sentence is missing a closing period. (Reported by Fidel Barrera Cruz, Georgia Tech.)
• Section 8.4 (print page 165): The identity in Corollary 8.13 is incorrect. It should read $$2^{2n} = \sum_{k=0}^n\binom{2k}{k}\binom{2n-2k}{n-k}$$. (Reported by Les Reid, Missouri State University.)
• Epilogue (print page 326): The paragraph about Yolanda incorrectly refers to Zori.