title: Regex - Match if there is any repeating lowercase letter
body: <p>What is a more succinct way of writing this regex? I wrote a script to generate this monstrosity, but I would prefer to understand the cleaner solution.</p>
  <pre><code>a{2,}|b{2,}|c{2,}|d{2,}|e{2,}|f{2,}|g{2,}|h{2,}|i{2,}|j{2,}|k{2,}|l{2,}|m{2,}|n{2,}|o{2,}|p{2,}|q{2,}|r{2,}|s{2,}|t{2,}|u{2,}|v{2,}|w{2,}|x{2,}|y{2,}|z{2,}
  </code></pre>
  <p>For example, it would match:</p>
  <pre><code>abcbb
  ababcaa
  abcazzba
  </code></pre>
  <p>But it would not match</p>
  <pre><code>abcabcdef
  abcde
  abc
  </code></pre>