t;</span> 3   X    o  X    o  X    o  o</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 4   X    o  X    o  X    o  o</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 5   X    o  X    o  X    o  o</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 6   X    o  X    o  X    o  o</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 7   X    o  X    o  X    o  o</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 8   X    o  X    o  X    o  o</span>
<span