title: Determine if a Bitcoin wallet address is "valid"
body: <p>I know it's possible to verify Bitcoin wallet addresses with Regex (<code>^[13][a-km-zA-HJ-NP-Z0-9]{26,33}$</code>) - but this is not 100% accurate and allows invalid addresses to be detected as valid.</p>
  
  <p>Is there publicly available C# algorithm that can verify bitcoin wallet addresses? I've been Googling for one, but couldn't find anything.</p>