Known bugs in version 1.2 of Building Blocks
=============================================

Thanks to everyone for reporting these bugs to me.  My plan is to keep
a stable version for the duration of this term (so, for example, the
page numbers don't keep changing) and then make a new version 
over winter break.

This file includes only easily-explained problems that are definitely
errors.  I also welcome comments on other issues (e.g. higher-level
organization, need for extra examples) that may not fit well into an
errata file.

   -- Margaret Fleck (mfleck@illinois.edu)

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Chapter 4, p. 48, last sentence in section 4.1: "notation" should be
"notion"

Chapter 4, p. 48, first paragraph in section 4.12:   the text refers
several times to "numbers."   In this context, numbers would always
be integers and it would have been more helpful to say "integers."

Chapter 5, p. 57, second paragraph: "The complement ... is all the
objects that aren't in A."  Better phrasing would have been "The
complement ... CONTAINS all the objects that aren't in A."

Chapter 5, p. 66, third line from the top:   "so" should be
capitalized and the period after "suppose that" should be removed.

Chapter 6, p. 73, definition of linear order.   "x >= y or y >= x"
probably should have used R or a curly >=, rather than a regular
numerical >= sign.

Chapter 6, p. 71, start of section 6.4:  in the definition of transitive,
the word "if" seems to have been set in math mode, so it's in italics
and the spacing is strange.

Chapter 10, p. 117, second paragraph:  "A graph is bipartite if and
only if its chromatic number is 2."   This should be "... if and only
if it is 2-colorable (i.e. its chromatic number is 1 or 2)."

Chapter 10, p. 117, third paragraph:  "ihe" for "the"

Chapter 10, p. 119, proof in section 10.5.  The claim says "12p + 9q"
but the proof is for "15p + 9q".  The difference between 12 and 15
happens to make very little difference in this case, but the two
should be consistent with one another.

Chapter 13, p. 147, last line:  "number" should be "numbers"

Chapter 13, p. 155:  the example grammar should have more space between
items on the righthand side of certain rules.  So
   S  --> NP  VP
   VP --> V NP  | V NP NP
   NP --> Det  N

Chapter 14, p. 173:  in the proof at the top of the page, x^3 should be
replaced by x^2 in several places

Chapter 15, p. 175:  the footnote is at the bottom of the next page,
due to some clumsy choice by the formatter.

Chapter 17, p. 197, last paragraph: "|S|+a files" should be "at least
|S|+1 files"

Chapter 18, page 207, the very last formula before section 18.7 begins
says (24 * 23 * 22 * 21) / (4 * 3 * 3) but the bottom portion is
supposed to be (4 * 3 * 2)

Chapter 20, p. 220, second-to-last paragraph:  "End states can be called
end states" should read "End states can be called final states"

Chapter 20, p. 224, 4th line of first paragraph and first line of
second paragraph mention a set that looks like the natural numbers
with a strange symbol for the exponent.   The exponent is supposed
to be 2, i.e. this is the set of pairs of natural numbers.

Chapter 20, p. 224, 4th line of first paragraph and first line of
second paragraph mention a set that looks like the natural numbers
with a strange symbol for the exponent.   The exponent is supposed
to be 2, i.e. this is the set of pairs of natural numbers.

Chapter 20, p. 224, 2nd line of second paragraph.  f_2(n,m) should be
2^n3^m (not 2^n3^n).

Chapter 20, p. 224, 5th line of 3rd paragraph:  jthe should be jth.

Chapter 20, p. 225, 4th and 5th lines of first paragraph:  same odd
exponent issue as on p. 224.   Again, the exponent is supposed to be 2.


Chapter 21, p. 240, end of second paragraph:  "5 colors" should
be "6 colors"

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