></section></td>
      <td style="text-align:left;">Sum without equation number.</td>
    </tr>
   <tr id="#30">
      <td style="text-align:right;">30</td>
      <td style="text-align:center;">&#128522;</td>
      <td style="text-align:left;">$$\sum_{i=1}^n$$ (2)</td>
      <td style="text-align:left;"><section class="eqno"><eqn><span class="katex-display"><span class="katex"><span class="katex-mathml"><math><semantics><mrow><msubsup><mo>∑</mo><mrow><mi>i</mi><mo>=</mo><mn>1</mn></mrow><mi>n</mi></msubsu