title: What are recursively enumerable sets?
body: <p>There seems to be a lot of <a href="http://en.wikipedia.org/wiki/Talk:Recursively_enumerable_set" rel="nofollow noreferrer">discussion</a> (and confusion) regarding the Wikipedia <a href="http://en.wikipedia.org/wiki/Recursively_enumerable" rel="nofollow noreferrer">article</a> on the topic. Other results Google throws up are not available for free public use. </p>
  
  <p>I would be interested in what you folks have to say.</p>