MathML 3 example for long div #1

[NSoiffer]

<math xmlns="http://www.w3.org/1998/Math/MathML">
<mlongdiv longdivstyle=":right=right">
  <mn> 7 </mn>
  <mn> 46</mn>

  <mn> 323</mn>

  <msgroup position="1">
    <msgroup>
      <mn> -28</mn>
      <msline position="-1" length="4"/>
    </msgroup>
    <msgroup position="-1">
      <mn> 43</mn>
      <mn> -42</mn>
      <msline length="2"/>
    </msgroup>
    <msgroup position="-1">
      <mn> 1</mn>
    </msgroup>
  </msgroup>
</mlongdiv>
</math>