<math xmlns="http://www.w3.org/1998/Math/MathML" id="p1.1.m1.1" class="ltx_Math" alttext="{\displaystyle f\rightarrow e}" display="inline">
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    <mrow id="p1.1.m1.1.4" xref="p1.1.m1.1.4.cmml">
      <mi id="p1.1.m1.1.1" xref="p1.1.m1.1.1.cmml">f</mi>
      <mo id="p1.1.m1.1.2" xref="p1.1.m1.1.2.cmml">→</mo>
      <mi id="p1.1.m1.1.3" xref="p1.1.m1.1.3.cmml">e</mi>
    </mrow>
    <annotation-xml encoding="MathML-Content" id="p1.1.m1.1b">
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        <ci id="p1.1.m1.1.2.cmml" xref="p1.1.m1.1.2">→</ci>
        <ci id="p1.1.m1.1.1.cmml" xref="p1.1.m1.1.1">𝑓</ci>
        <ci id="p1.1.m1.1.3.cmml" xref="p1.1.m1.1.3">𝑒</ci>
      </apply>
    </annotation-xml>
    <annotation encoding="application/x-tex" id="p1.1.m1.1c">{\displaystyle f\rightarrow e}</annotation>
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</math>

<math xmlns="http://www.w3.org/1998/Math/MathML" display="block" alttext="{\displaystyle f\rightarrow e}">
  <semantics>
    <mrow class="MJX-TeXAtom-ORD">
      <mstyle displaystyle="true" scriptlevel="0">
        <mi>f</mi>
        <mo stretchy="false">&#x2192;<!-- → --></mo>
        <mi>e</mi>
      </mstyle>
    </mrow>
    <annotation encoding="application/x-tex">{\displaystyle f\rightarrow e}</annotation>
  </semantics>
</math>