title: How to concatenate strings as year month without using for loops
body: <p>I am trying to create the strings <code>year,month</code> for several years (from 199701 to 200612). I can do it using for loops, is there a way to do this without using loops? </p>
  
  <p>My goal:</p>
  
  <pre><code>#1997 01 to 2006 12
  199701
  199702
  199703
  199704
  199705
  199706
  199707
  199708
  199709
  199710
  199711
  199712
  199801
  .....
  </code></pre>