title: Run Cron job every N minutes plus offset
body: <p><code>*/20 * * * *</code></p>
  
  <p>Ensures it runs every 20 minutes, I'd like to run a task every 20 minutes, starting at 5 past the hour, is this possible with Cron?  Would it be:</p>
  
  <p><code>5/20 * * * *</code>  ?</p>