title: All unique multiplication products
body: <p>I'd like to obtain all <em>unique</em> products for a given vector. </p>
  
  <p>For example, given <code>a</code>:</p>
  
  <pre><code>a = [4,10,12,3,6]
  </code></pre>
  
  <p>I want to obtain a matrix that contains the results of:</p>
  
  <pre><code>4*10
  4*12
  4*3
  4*6
  10*12
  10*3
  10*6
  12*3
  12*6
  3*6
  </code></pre>
  
  <p>Is there a short and/or quick way of doing this in MATLAB?</p>
  
  <p><strong>EDIT</strong>: <code>a</code> may contain duplicate numbers, giving duplicate products - and these must be kept. </p>