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      <mi mathvariant="normal" id="p1.1.m1.1.3" xref="p1.1.m1.1.3.cmml">∞</mi>
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<math class="mwe-math-element" xmlns="http://www.w3.org/1998/Math/MathML"><mrow data-mjx-texclass="ORD"><mstyle displaystyle="true" scriptlevel="0"><mi>r</mi><mo accent="false">&#x2192;</mo><mi mathvariant="normal">&#x221E;</mi></mstyle></mrow></math>