title: Creating numpy array with different steps
body: <p>I would like to create an array like the following:</p>
  
  <pre><code># 0 | 4 | 8 | 16 | 32
  </code></pre>
  
  <p>In which, each element except the first, is the double of the previous one.
  I can create this smaller through an iteration and so on.</p>
  
  <p>However, as Python provides a lot of one-liner functions, I was wondering if there is one that allows me to do that.</p>