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<html>
  <head>
    <title>attribute lspace rspace dynamic</title>
    <meta charset="utf-8"/>
  </head>
  <body>

    <math><mi>x</mi><mo lspace="3em">X</mo><mi>y</mi></math><br/>
    <math><mi>x</mi><mo rspace="5em">X</mo><mi>y</mi></math><br/>
    <math><mi>x</mi><mo lspace="3em" rspace="5em">X</mo><mi>y</mi></math><br/>
    <math><mi>x</mi><mo rspace="5em">X</mo><mi>y</mi></math><br/>
    <math><mi>x</mi><mo lspace="3em">X</mo><mi>y</mi></math><br/>
    <math><mi>x</mi><mo>X</mo><mi>y</mi></math>

  </body>
</html>