Misprints in Combinatorics

In the list, "line -n" means n lines up from the bottom. I am grateful to Bruce Sagan, Jonathan Hall, and their students, and to Jacobus Swarts, for many of the items on this list.

• page 31, line -3: "Exercise 12" should be "Exercise 14"
• page 31, line -2: "Exercise 13" should be "Exercise 15"
• page 44, line -2: "k is odd" should be "n is odd"
• page 45, line 12: "Section 3.11" should be "Section 3.12"
• page 61, line -4: "2n-2" should be "2n"
• page 62, line -5: This double exponential is underfined as a formal power series
• page 72, Ex 20(a): "1-t²" should be "1-t"
• page 81, line 7: "than" should be "that"
• page 97-98: There is no Exercise 2
• page 98, Exercise 3(c): The sequence should be (x₀, ..., x_n-1), not (x₁, ..., x_n); and i should run from 0 to n-2 instead of 1 to n-1. (Spotted by Nik Ruskuc.)
• page 102, line 3: "(n-|A|!)" should be "(n-|A|)!"
• Page 103, line -13: r_i >= k_j should be r_i <= k_j. (Spotted by Nik Ruskuc.)
• Page 104, line -9: replace "suppse" by "suppose".
• Page 105, paragraph after Remark 2: The sets in F should be {x} union U and {x} union V, and their complements {y} union V and {y} union U. (Spotted by Nik Ruskuc.)
• Page 107: Bruce Sagan says: "It was brought to my attention in class today that in order for Theorem 8.1.2 to be true for n=3 you need to allow n=m, while on page 107 you insist that n>m. It's a minor point, but there is nothing wrong with allowing n=m=l."
• page 111: note that three of the lines of the STS are not shown in the figure
• Page 112: to get a subsystem of order 7, we require w > 1 rather than w > 0. (Spotted by Jacobus Swarts)
• page 131, line 4: "puropse" should be "purpose"
• page 131, definition of projective plane: second B should be X. (Spotted by Jacobus Swarts)
• page 134, second last paragraph of the proof of (9.5.6): L' should be L'' twice ("...parallel to the same line L'' are ..." and "... are disjoint from L'', which ..."). (Spotted by Dudley Stark.)
• page 137, line 2: W=v should be W+v
• page 137, line -13: delete opening parenthesis
• page 137, line -5: r-1 should be r+1 in two places
• page 137, line -2: t+1 should be t-1
• page 138: The use of [*,*,*] for [x,y,z] and [a,b,c] is confusing.
• page 141, line -13: "6^th" should be "i^th"
• page 141, line -3: "Fact 4" should be "Fact 3"
• page 145, line -5: The degree of a net is defined to be the number of parallel classes.
• page 192, 8th line of proof: represesnted -> represented (Spotted by Jacobus Swarts)
• page 198, Proposition 12.6.1(b): the n in the index of the last lattice in the list should be r. (Spotted by Jacobus Swarts)
• page 200, line 10: "1 <= i <= n" should be "1 <= k <= n"
• page 202, line 1: One also needs to check that this mu is in I(P₁ x ... x P_k) (which is easy, but should be noted).
• page 202, line -11: "precisely" should be "dually"
• page 203, Exchange axiom: z should not be in Y. (Spotted by Yatin Nandwani).
• page 260, line after displayed equation: inequality -> equality. (Spotted by Jacobus Swarts)
• page 261, line 1: mod 3 -> mod 2. (Spotted by Jacobus Swarts)
• page 261, line 13: "16.1.2" should be "16.1.3"
• page 263, line -6: "root" should be "double root"
• page 268: "Haramard" should be "Hadamard" (spotted by Colton Magnant)
• page 269, Exercise 1: "v+1 divides b(k+1)" should read "k+1 divides b(v+1)". (Spotted by Ron Gould)
• page 319, line 8: "specail" should be "special"
• page 320, line -9: "exampes" should be "examples"
• page 353, projective plane entry: "102" should be "103"

Peter J. Cameron
p.j.cameron(at)qmul.ac.uk 19 October 2005.