title: mkdir: cannot create directory ‘/usr/local/n/versions’: Permission denied
body: <p>When I run <code>npm install n -g</code> on my computer (Ubuntu), I have these errors:</p>
  
  <pre><code>➜  ~  npm install -g n
  
  /home/joes/.nvm/v0.10.38/bin/n -&gt;          /home/joes/.nvm/v0.10.38/lib/node_modules/n/bin/n
  n@2.0.2 /home/joes/.nvm/v0.10.38/lib/node_modules/n`
  
  ➜  ~  n
  
  mkdir: cannot create directory ‘/usr/local/n/versions ’: Permission denied
  mkdir: cannot create directory ‘/usr/local/n/versions ’: Permission denied
  find: '/usr/local/n/versions': No such file or directory`
  Error: no installed version
  </code></pre>