title: Combine columns in a Pandas DataFrame to a column of lists in a DataFrame
body: <p>Consider the following <code>DataFrame</code>.</p>
  
  <pre><code>n  v1 v2 v3 v4 v5
  0   1  2  3  4  5
  1   1  2  3  4  5
  2   1  2  3  4  5
  </code></pre>
  
  <p>For each row, I want to add the values of <code>v2</code>, <code>v3</code>, <code>v4</code> to a list and multiply the values in the list with <code>v5</code> and put the result into a new column <code>v6</code> such that I end up with a <code>DataFrame</code> like this:</p>
  
  <pre><code>n  v1  v6
  0   1  [10, 15, 20]
  1   1  [10, 15, 20]
  2   1  [10, 15, 20]
  </code></pre>
  
  <p>How can I achieve this in Pandas?</p>