msup-09.test

<<< native
[ ESuper
    (ENumber "2")
    (ESuper (ENumber "3") (ESuper (ENumber "4") (ENumber "5")))
, ESymbol Rel "="
, ESuper
    (ENumber "2")
    (ESuper
       (ENumber "3")
       (ESuper
          (ENumber "4") (ESuper (ENumber "5") (EPhantom (ENumber "6")))))
]
>>> mml
<?xml version='1.0' ?>
<math display="block" xmlns="http://www.w3.org/1998/Math/MathML">
  <mrow>
    <msup>
      <mn>2</mn>
      <msup>
        <mn>3</mn>
        <msup>
          <mn>4</mn>
          <mn>5</mn>
        </msup>
      </msup>
    </msup>
    <mo>=</mo>
    <msup>
      <mn>2</mn>
      <msup>
        <mn>3</mn>
        <msup>
          <mn>4</mn>
          <msup>
            <mn>5</mn>
            <mphantom>
              <mn>6</mn>
            </mphantom>
          </msup>
        </msup>
      </msup>
    </msup>
  </mrow>
</math>