<p>Here is a dummy piece of R code.</p>

<pre><code>pca &lt;- prcomp(matrix(rnorm(10*10), ncol=10))
pca$x
    pca$rotation
</code></pre>

<p>The third line appears indented, whereas it is not in the source. Removing the <code>$</code> sign from the line unindents it, so it looks like a collision between MathJax and Markdwon (at least Showdown).</p>

<p>How can I use the <code>$</code> notation in R code while avoiding this?</p>
