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\framebox{\parbox\courseheader{\large Introduction to Theory of Computing\hfill Homework 8\\ 
CS 4810 Spring 2022\hfill Due Monday, 18 April 2022}}
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\begin{enumerate}
\item
Do Homework 8 Exercise 2(a)--(c), p.~309. For (a), mimic the formal definition of Turing machines in Lecture 28.

\item
Describe a deterministic Turing machine that accepts the set $\set{a^{3^n}}{n\geq 0}$. Your description should be \emph{precise} but \emph{informal}---that is, do not give a list of transitions, but just describe in English how the machine operates. Model your description on Examples 29.1, p.~216 and 29.2, p.~217 in the text for the TMs that accept $\set{ww}{w\in\Sigma^*}$ and strings of prime length, respectively.
\end{enumerate}

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