Typo in Proof of Theorem 5.21

[twjudson]

Potential typo in Section 5.2 of the book. In the proof of Theorem 5.21, you mention that if an element of D_n sends 1 to k and then 2 to k-1, then the element is sr^k. But isn’t it actually r^ks? Notice that unless n is even and k=n/2, then sr^k does not send 1 to k.