<<< native
[ EText
    TextNormal
    "Displayed nested fractions are normal size at the first level,\160"
, EFraction
    NormalFrac
    (ESuper (ENumber "1") (ESqrt (ENumber "6")))
    (EGrouped
       [ ESqrt (ENumber "2")
       , ESymbol Bin "+"
       , EFraction
           NormalFrac
           (ENumber "1")
           (EGrouped
              [ ESqrt (ENumber "3")
              , ESymbol Bin "+"
              , EFraction
                  NormalFrac
                  (ENumber "1")
                  (EGrouped
                     [ ESqrt (ENumber "4")
                     , ESymbol Bin "+"
                     , EFraction
                         NormalFrac
                         (ENumber "1")
                         (EGrouped
                            [ ESqrt (ENumber "5")
                            , ESymbol Bin "+"
                            , EFraction
                                NormalFrac
                                (ENumber "1")
                                (EGrouped
                                   [ ESqrt (ENumber "6") , ESymbol Bin "+" , EIdentifier "\8230" ])
                            ])
                     ])
              ])
       ])
, EText
    TextNormal
    "\160script size at second level, and script-script size at all more nested levels."
]
>>> omml
<?xml version='1.0' ?>
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      <m:t>Displayed nested fractions are normal size at the first level, </m:t>
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          <m:sup>
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                <m:degHide m:val="1" />
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              <m:deg />
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          <m:radPr>
            <m:degHide m:val="1" />
          </m:radPr>
          <m:deg />
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          </m:e>
        </m:rad>
        <m:r>
          <m:rPr>
            <m:sty m:val="p" />
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          <m:t>+</m:t>
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          <m:num>
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            <m:rad>
              <m:radPr>
                <m:degHide m:val="1" />
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              <m:deg />
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                  <m:t>3</m:t>
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            </m:rad>
            <m:r>
              <m:rPr>
                <m:sty m:val="p" />
              </m:rPr>
              <m:t>+</m:t>
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            <m:f>
              <m:fPr>
                <m:type m:val="bar" />
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              <m:num>
                <m:r>
                  <m:t>1</m:t>
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              <m:den>
                <m:rad>
                  <m:radPr>
                    <m:degHide m:val="1" />
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                  <m:deg />
                  <m:e>
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                  </m:e>
                </m:rad>
                <m:r>
                  <m:rPr>
                    <m:sty m:val="p" />
                  </m:rPr>
                  <m:t>+</m:t>
                </m:r>
                <m:f>
                  <m:fPr>
                    <m:type m:val="bar" />
                  </m:fPr>
                  <m:num>
                    <m:r>
                      <m:t>1</m:t>
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                    <m:rad>
                      <m:radPr>
                        <m:degHide m:val="1" />
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                      <m:deg />
                      <m:e>
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                          <m:t>5</m:t>
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                    </m:rad>
                    <m:r>
                      <m:rPr>
                        <m:sty m:val="p" />
                      </m:rPr>
                      <m:t>+</m:t>
                    </m:r>
                    <m:f>
                      <m:fPr>
                        <m:type m:val="bar" />
                      </m:fPr>
                      <m:num>
                        <m:r>
                          <m:t>1</m:t>
                        </m:r>
                      </m:num>
                      <m:den>
                        <m:rad>
                          <m:radPr>
                            <m:degHide m:val="1" />
                          </m:radPr>
                          <m:deg />
                          <m:e>
                            <m:r>
                              <m:t>6</m:t>
                            </m:r>
                          </m:e>
                        </m:rad>
                        <m:r>
                          <m:rPr>
                            <m:sty m:val="p" />
                          </m:rPr>
                          <m:t>+</m:t>
                        </m:r>
                        <m:r>
                          <m:t>…</m:t>
                        </m:r>
                      </m:den>
                    </m:f>
                  </m:den>
                </m:f>
              </m:den>
            </m:f>
          </m:den>
        </m:f>
      </m:den>
    </m:f>
    <m:r>
      <m:rPr>
        <m:nor />
        <m:sty m:val="p" />
      </m:rPr>
      <m:t> script size at second level, and script-script size at all more nested levels.</m:t>
    </m:r>
  </m:oMath>
</m:oMathPara>