Page 240

Location: Chapter 25, solution to Problem 4

It is (lines 3-4 of page)

Therefore n belongs to the set \mathscr{S}^\star (because A computes S^\star, hence if n didn't belong to S^\star, then...

It should become

Therefore n belongs to the set \mathscr{S}^\star (because A computes \mathscr{S}^\star, hence if n didn't belong to \mathscr{S}^\star, then...

Short explanation

A simple typographic mistake.