Corrections on exceptTowYFFTA_519: 

02/20/07: pp. 398--399: The essential correction is to conclude T_{n,a}(x) = D_{n,a}^*(x)=D_{n,a}(2x)/2 

with D_{n,a}(x) the degree n Dickson Polynomial with parameter a. 

p. 398: l -4: Change "readily identifiable contant times" to "related to"

l -3: Change "D_{n,a}(x)=a^{n-1}T_{n,a}(x)" to "D_{n,a}(2x)/2 = D^*_{n,a}(x) = T_{n,a}(x)"

p. 399: l 1: Wrap "x^n + (a/x)^n" in parens. 

l 3: Change D_{n,a}(m_a(x)) to D_{n,a}^*(m_a(x)) 

l 4: Change x + b/x to m_b(x). 

l 10: Change line after "properties" to "(with $\infty \mapsto \infty$) $T_{n,a}(x)=D^*_{n,a}(x)$."

10/15/09

p. 418: In the penultimate paragraph of Section 7.2.4, discussing where exceptionality enters in % Katz's result, I added "and we know exactly when that happens (as in Lem. 1.3 and ¬ß6.1 ).