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        <identifier>oai:www.ideals.illinois.edu:2142/68190</identifier>
        <datestamp>2023-07-11</datestamp>
        <setSpec>col_2142_5131</setSpec>
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        <thesis xmlns="http://www.ndltd.org/standards/metadata/etdms/1.1/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:dc="http://purl.org/dc/elements/1.1/" xsi:schemaLocation="http://www.ndltd.org/standards/metadata/etdms/1.1/ http://www.ndltd.org/standards/metadata/etdms/1.1/etdms11.xsd http://purl.org/dc/elements/1.1/ http://www.ndltd.org/standards/metadata/etdms/1.1/etdmsdc.xsd">
          <dc:creator>Haring-Smith, Robert Henry</dc:creator>
          <dc:date>2014-12-14T13:09:52Z</dc:date>
          <dc:date>2014-12-14T13:09:52Z</dc:date>
          <dc:date>10000-01-01</dc:date>
          <dc:date>1981</dc:date>
          <dc:date>1981</dc:date>
          <dc:description>With any finitely generated presentation (pi) =  of a group G, one can associate a formal language WP(,0)((pi)), the reduced word problem of (pi), consisting of all words on the generators and their inverses which are equal to the identity of G but have no proper prefix equal to the identity. A general problem, then, is to determine what the nature of the reduced word problem implies about the structure of the group G, or, conversely, how the properties of G affect WP(,0)((pi)).</dc:description>
          <dc:description>The simple languages form a class of prefix-free languages properly contained in the class of context-free languages. Simple languages can be accepted by one-state deterministic pushdown automata which read an input symbol at every step in a computation. The main results of the thesis are:</dc:description>
          <dc:description>Theorem. A finitely generated presentation (pi) of a group G has a simple reduced word problem if and only if there are only a finite number of simple closed paths passing through each vertex in the Cayley diagram of (pi).</dc:description>
          <dc:description>Theorem. A group G has a presentation with a simple reduced word problem if and only if G is the free product of a finitely generated free group and a finite number of finite groups.</dc:description>
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8203480.pdf: 2129536 bytes, checksum: 470dcb09d22e97b91c16b509fb2ca804 (MD5)
  Previous issue date: 1981</dc:description>
          <dc:description>Embargo set by: Seth Robbins for item 68368
Lift date: Forever
Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs</dc:description>
          <dc:description>Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs</dc:description>
          <dc:description>U of I Only</dc:description>
          <dc:description>77 p.</dc:description>
          <dc:description>Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1981.</dc:description>
          <dc:identifier>http://hdl.handle.net/2142/68190</dc:identifier>
          <dc:identifier>(UMI)AAI8203480</dc:identifier>
          <dc:language>eng</dc:language>
          <dc:subject>Mathematics</dc:subject>
          <dc:title>Groups and Simple Languages</dc:title>
          <dc:type>text</dc:type>
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            <department>Mathematics</department>
            <discipline>Mathematics</discipline>
            <grantor>University of Illinois at Urbana-Champaign</grantor>
            <level>Dissertation</level>
            <name>Ph.D.</name>
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