<<< native
[ ESub
    (EIdentifier "m")
    (EGrouped [ ENumber "1" , ESymbol Ord "\8291" , ENumber "2" ])
]
>>> omml
<?xml version='1.0' ?>
<m:oMathPara>
  <m:oMathParaPr>
    <m:jc m:val="center" />
  </m:oMathParaPr>
  <m:oMath>
    <m:sSub>
      <m:e>
        <m:r>
          <m:t>m</m:t>
        </m:r>
      </m:e>
      <m:sub>
        <m:r>
          <m:t>1</m:t>
        </m:r>
        <m:r>
          <m:rPr>
            <m:sty m:val="p" />
          </m:rPr>
          <m:t>&#8291;</m:t>
        </m:r>
        <m:r>
          <m:t>2</m:t>
        </m:r>
      </m:sub>
    </m:sSub>
  </m:oMath>
</m:oMathPara>