title: Detecting sequence of at least 3 sequential numbers from a given list
body: <p>I have a list of numbers e.g.  21,4,7,9,12,22,17,8,2,20,23</p>
  
  <p>I want to be able to pick out sequences of sequential numbers (minimum 3 items in length), so from the example above it would be 7,8,9 and 20,21,22,23.</p>
  
  <p>I have played around with a few ugly sprawling functions but I am wondering if there is a neat LINQ-ish way to do it.</p>
  
  <p>Any suggestions?</p>
  
  <p><strong>UPDATE:</strong></p>
  
  <p>Many thanks for all the responses, much appriciated. Im am currently having a play with them all to see which would best integrate into our project. </p>