# Formal Languages and Automata

1. Oct 25, 2011

### Ted123

1. The problem statement, all variables and given/known data

[PLAIN]http://img577.imageshack.us/img577/1948/dfav.jpg [Broken]

3. The attempt at a solution

For the first part, am I interpreting the langauage L correctly as words of length multiples of 4? Would the following DFA accept this L:
[PLAIN]http://img685.imageshack.us/img685/6026/dfa2.jpg [Broken]

For the 2nd part, is the language recognised by the DFA: $L(\mathcal{A})=\{ab\}^{*} = \{ \varepsilon, ab, (ab)^2, (ab)^3, \cdots \} = \{ (ab)^n : n\geq 0 \}$ ?

How do I express the language recognised by the final DFA $\mathcal{B}$ ?

Last edited by a moderator: May 5, 2017