title: Simple phone number regex, starting zero optional, no separators
body: <p>I'm trying to build a regex that works specifically for my country, Venezuela, for our mobile phone providers. So, the number can only begin with 0412 | 0414 | 0416 | 0424 | 0426, and also I'm trying to make the starting 0 optional. From there on, the number is always 7 digits long. Meaning that the complete phone number is 10 to 11 digits long, and the first 4 must be either 412 | 414 | 416 | 424 | 426, with an optional leading zero. All of this is intended for a C# application. Thanks!</p>
  
  <p>I have tried with the following and variations thereof:</p>
  
  <pre><code>((0?(412|414|416|424|426))\d{3}|\d{4})\d{7}
  </code></pre>
  
  <p>and <code>www.regexr.com</code> (great site, by the way)</p>