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<?xml version="1.0"?>
    <allpages apcontinue="Charles_Sanders_Peirce" />
      <p pageid="323" ns="0" title="Boolean-valued function" />
      <p pageid="321" ns="0" title="Boolean domain" />
      <p pageid="322" ns="0" title="Boolean function" />
      <p pageid="149" ns="0" title="Center" />
      <p pageid="150" ns="0" title="Center (mathematics)" />
      <p pageid="151" ns="0" title="Center of a group" />
      <p pageid="152" ns="0" title="Center of a ring" />
      <p pageid="148" ns="0" title="Centre" />
      <p pageid="8" ns="0" title="Characteristic (mathematics)" />
      <p pageid="11" ns="0" title="Characteristic subgroup" />