# Lessons in Play

## Errata

• (Apr 3, 2007) Missing entries in the index:
• Berlekamp, Elwyn, 6, 51, 112, 215
• Bouton, Charles, 41
• Conway, John, 6, 51
• Demaine, Eric, 278
• Fraenkel, Aviezri, 278
• Grundy, Patrick, 41
• Guy, Richard, 6, 41, 51
• Sprague, Roland, 41
• (Nov 28, 2007) Page 28, line -3: change four to fourteen.
• (Nov 28, 2007) Page 29, line -4: change parley to parlay.
• (Apr 5, 2007) Pages 59-62, Section 3.4: Outcome classes for Domineering Rectangles are analyzed in Lachmann, Moore, and Rapaport, Who Wins Domineering on Rectangular Boards?, in More Games of No Chance, pages 307-315. For 2xn and 3xn domineering, see Elwyn Berlekamp, Blockbusting and Domineering, Journal of Combinatorial Theory, September 1988.
• (Jan 10, 2009) Page 79: (typesetting) comma missing after each of four Js.
• (Apr 3, 2007) Page 83, problem 1: The second position labeled i should be j.
• (May 24, 2007) Page 88: The displayed equation should read
    2 = {1|} = {{0|}|} = {{{|}|}|}
• (May 24, 2007) Pages 95-96: Starting position in example 5.30 is bugged. The second summand should have a blank initial square rather than a white piece; same with the third summand. These two errors are duplicated on the next displayed position, and in the second row of the table on the following page. In summary, the position should be:
    xo + .ox + .o + oox
which is
    -3/2 + 7/4 + -2 + 13/8
• (Apr 3, 2007) Page 111, Conjecture 5.57: Despite what is stated in the preceding paragraph, the fascinating result was discovered and proved by Aaron Siegel in October 2005.
• (May 18, 2007) Page 118: In the first diagram, middle of page, L and R should be reversed.
• (Apr 3, 2007) Page 128, first displayed equations: Elsewhere we use a | for "such that" in set notation rather than a :
• (Jan 18, 2008) Page 136, line 1: The canonical form of ^ [not ^*], which is...
• (Jan 10, 2009) Page 146, last line 2nd paragraph: Remove second of two consecutive 0s changing ...14002... to ...1402...
• (Jan 10, 2009) Page 150, line -4: {G(n - a), ..., G(n) - 1} should be {G(n - a), ..., G(n - 1)}.
• (Jan 18, 2008) Page 164, line 3: Change 2_L to 2_R
• (Jan 18, 2008) Page 165, first displayed equation, and subsequent lines: Replace G-G^L by G^L-G in three places.
• (Jan 10, 2009) Page 191; incomplete errata: (top of page) The second sentence of the proof is nonsense. Argue, instead, that .11112 - G^{RL} is greater or incomparable with .111112 - G...
• (Jan 18, 2008) Page 194, sentance after definition 9.26, replace "G or H" with "G+X or H+X".
• (Jan 18, 2008) Page 195, line 3 of proof of Theorem 9.29: Replace "G_1+H_1 ~ G_2+H_2" with "G_1+G_2 ~ H_1+H_2"
• (Jan 18, 2008) Page 196, line 3: Replace second sentence with the following (writing * for the far-star symbol): Choosing X=-H+v in the definition of ~*, (G-H)+v* has the same outcomes as (H-H)+v* = ... (Two changes: Choose X=-H+v (not -G) and (H-H) (not G-G).)
• (Jan 26, 2008) Page 200, 5th bullet, end of line AW(^) -> AW(^^)
• (Jan 18, 2008) Page 214, w.4 second line: my -> may
• (Jan 18, 2008) Page 247, first line of solution to 5.45, {x|x} -> {x|-x}
• (Jan 18, 2008) Page 268, endnim: Change first "1,3,1" to "1,3,3"
• (Apr 3, 2007) Page 229, problem 6: For part (c) append, "Hint: Add a new number, an+1, which is the mean of a1, ..., an. Either the arithmetic or the geometric mean will work."
• (Oct 11, 2007) Page 239, Exercise 1.17 solution: The scores should be 8-4 and 10-2, respectively.
• (Dec 4, 2007) Page 243, solution to 4.26 #2: There are options to 1/2 and -1/2, respectively, so the middle expression should read {0, *, -1, -1/2 | 0, *, 1, 1/2}.
• (May 18, 2007) Page 265, CLOBBER: Delete the last sentence, "Right moves leftward."
• (Dec 18, 2007) Page 236, lines 9 and 13 of the script should use === rather than == in the latest version of cgsuite:
if (pos[i] === 'L' or pos[i] === 'G') then
if (pos[i] === 'R' or pos[i] === 'G') then

• (Jan 10, 2009) Page 268, Endnim: The sample game has an illegal Left move which leaves the position unchanged.
• (Jan 10, 2009) Page 275, line -2: Change of a global board positions'' to of global board positions''.
• (Jan, 2009) GLOBAL CHANGE: We ought to have used \cdot in place of empty options throught the book.