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August 27th, 2011, 11:33 AM   #1
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Sets under union

can some give me a example as well as prove of this

Prove that Regular Sets are NOT closed under infinite union. (A counterexample suffices).
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August 27th, 2011, 02:01 PM   #2
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Re: Sets under union

What have you tried so far? I would usually look at some languages that you know aren't regular to see if I can form them as an infinite union of regular languages. Actually, you should be able to do this for any nonregular language.
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