>
      <td style="text-align:left;">simple equation including special html character.</td>
    </tr>
   <tr id="#4">
      <td style="text-align:right;">4</td>
      <td style="text-align:center;">&#128522;</td>
      <td style="text-align:left;">$a \backslash$</td>
      <td style="text-align:left;"><p><eq><span class="katex"><span class="katex-mathml"><math><semantics><mrow><mi>a</mi><mi mathvariant="normal">\</mi></mrow><annotation encoding="application/x-tex">a \backslash</annotation></semantics></math