title: How to grep a line start with #* using grep in R
body: <p>I have a question about Grep in R: How to specify that the element start with <code>#*</code> following  (without space) by some character or number ?</p>
  
  <pre><code>titre_index &lt;- grep('#\*', test)
  </code></pre>
  
  <blockquote>
    <p>Error: '*' is an unrecognized escape in character string starting "'#*"</p>
  </blockquote>