ass="dv">12</span>, <span class="dt">c =</span> <span class="dv">13</span><span class="op">:</span><span class="dv">18</span>)</span>
<span id="cb2-2"><a href="#cb2-2" aria-hidden="true"></a>DF</span>
<span id="cb2-3"><a href="#cb2-3" aria-hidden="true"></a><span class="co">#   ID a  b  c</span></span>
<span id="cb2-4"><a href="#cb2-4" aria-hidden="true"></a><span class="co"># 1  b 1  7 13</span></span>
<span id="cb2-5"><a href="#cb2-5" aria-hidden="true"></a><span class="co"># 2  b 2  8 14</span></span>
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