title: Create converging list of integers
body: <p>I need to create a converging list of integers that, for any given length, will be ordered:</p>
  <p>largest, smallest, second largest,second smallest,third largest,third smallest...</p>
  <p>until we run out of numbers.</p>
  <p>E.g.</p>
  <pre><code>def converging_list(val):
     lst = some clever function
     return lst
  
  converging_list(7)
  Output: [7,0,6,1,5,2,4,3]
  </code></pre>
  <p>How would I do this?</p>