title: How do I ensure a text box is alphanumeric but without a leading digit?
body: <p>My web application contains a text box for which I would like to restrict its input.  I would like to prevent the user from entering text that:</p>
  
  <ul>
  <li>Starts with white space</li>
  <li>Starts with something other than a digit</li>
  <li>Contains alphanumeric characters after the leading character.</li>
  </ul>
  
  <p>Thank you for your suggestions!</p>