title: Copy every nth line from one sheet to another
body: <p>I have an Excel spreadsheet with 1 column, 700 rows. I care about every seventh line. I don't want to have to go in and delete the 6 rows between each row I care about. So my solution was to create another sheet and specify a reference to each cell I want.</p>
  
  <pre><code>=sheet1!a1
  =sheet1!a8
  =sheet1!a15
  </code></pre>
  
  <p>But I don't want to type in each of these formulas ... `100 times.I thought if I selected the three and dragged the box around, it would understand what I was trying to do, but no luck.</p>
  
  <p>Any ideas on how to do this elegantly/efficiently?</p>