This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: language? If “yes”, then explain why? If “no”, then justify your answer with a concrete counterexample. 3. Prove that there exists an undecidable language that is a subset of { 1 } * . Hint: The key is to be able to encode strings from { , 1 } * using strings from { 1 } * . Develop your proof around this idea. 4. Prove that a language A is decidable if and only if A ≤ m * 1 * . (Both directions need to be proved.) 5. Let S = {a M A M is a TM and L ( M ) = {a M A}} . Prove that neither S nor ¯ S is Turingrecognizable. Spring 10: CSci 4011—Formal Languages and Automata Theory Homework Cover Page (Please fll in and staple to the Front oF your homework) Name (print): Student ID #: Homework #: Discussion Section registered for (check one): c Sec. 2 (11:15 a.m.–12:05 p.m.; ShengWen Wang) c Sec. 3 (12:20 p.m.–01:10 p.m.; Maitreyi Nanjanath) c Sec. 4 (10:10 a.m.–11:00 a.m.; ShengWen Wang)...
View
Full Document
 Spring '08
 NADATHUR
 Formal language, Regular expression, homework cover page, Languages and Automata Theory, CSci 4011—Formal Languages

Click to edit the document details