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<article
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    xmlns:xlink="http://www.w3.org/1999/xlink" dtd-version="3.0" xml:lang="en" article-type="mini-review">
  <front>
    <journal-meta>
      <journal-id journal-id-type="publisher-id">IJMEBAC</journal-id>
      <journal-title-group>
        <journal-title>International Journal of Mathematical, Engineering, Biological and Applied Computing</journal-title>
      </journal-title-group>
      <issn pub-type="epub"></issn>
      <issn pub-type="ppub"></issn>
      <publisher>
        <publisher-name>Science Publications</publisher-name>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="doi">10.31586/ijmebac.2022.335</article-id>
      <article-id pub-id-type="publisher-id">IJMEBAC-335</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Mini Review</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>
          Graph Coloring Solutions to Queen Graphs
        </article-title>
      </title-group>
      <contrib-group>
<contrib contrib-type="author">
<name>
<surname>Marappan</surname>
<given-names>Raja</given-names>
</name>
</contrib>
      </contrib-group>
      <pub-date pub-type="epub">
        <day>16</day>
        <month>06</month>
        <year>2022</year>
      </pub-date>
      <volume>1</volume>
      <issue>1</issue>
      <history>
        <date date-type="received">
          <day>16</day>
          <month>06</month>
          <year>2022</year>
        </date>
        <date date-type="rev-recd">
          <day>16</day>
          <month>06</month>
          <year>2022</year>
        </date>
        <date date-type="accepted">
          <day>16</day>
          <month>06</month>
          <year>2022</year>
        </date>
        <date date-type="pub">
          <day>16</day>
          <month>06</month>
          <year>2022</year>
        </date>
      </history>
      <permissions>
        <copyright-statement>&#xa9; Copyright 2022 by authors and Trend Research Publishing Inc. </copyright-statement>
        <copyright-year>2022</copyright-year>
        <license license-type="open-access" xlink:href="http://creativecommons.org/licenses/by/4.0/">
          <license-p>This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/</license-p>
        </license>
      </permissions>
      <abstract>
        Graph coloring, an NP-complete problem is used in many real-world applications. The minimum color, that is, the chromatic number of a connected graph is determined using different soft computing strategies. This article gives some of the solutions obtained for queen graphs using evolutionary methods.
      </abstract>
      <kwd-group>
        <kwd-group><kwd>Graph Coloring; Chromatic Number; Soft Computing; Evolutionary Methods</kwd>
</kwd-group>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec1">
<title>Introduction</title><p>Let G be the connected graph with <italic>n</italic> vertices and <italic>e</italic> edges. The chromatic number of G, &#x26;#x003c7;(G) is the least color count required to color the vertex set V(G) such that no two adjacent vertices are assigned with the same integer [
<xref ref-type="bibr" rid="R1">1</xref>]. &#x26;#x003c7;(G) is determined using different soft computing strategies [
<xref ref-type="bibr" rid="R2">2</xref>,<xref ref-type="bibr" rid="R3">3</xref>]. This research gives &#x26;#x003c7;(G) and the optimal coloring assignments for some of the queen graphs that are obtained using the soft computing strategies.</p>
</sec><sec id="sec2">
<title>Queen Graphs Color Assignments</title><title>2.1. queen5_5.col</title><p>&#x26;#x003c7;(G) = 5</p>
<p>Optimal color assignments:</p>
<p>(3 4 2 5 1 2 5 1 3 4 1 3 4 2 5 4 2 5 1 3 5 1 3 4 2)</p>
<p>(1 2 3 4 5 3 4 5 1 2 5 1 2 3 4 2 3 4 5 1 4 5 1 2 3)</p>
<p>(2 3 4 5 1 4 5 1 2 3 1 2 3 4 5 3 4 5 1 2 5 1 2 3 4) </p>
<p>(3 1 4 5 2 4 5 2 3 1 2 3 1 4 5 1 4 5 2 3 5 2 3 1 4)</p>
<p>(1 2 3 4 5 4 5 1 2 3 2 3 4 5 1 5 1 2 3 4 3 4 5 1 2)</p>
<p>(3 4 1 5 2 1 5 2 3 4 2 3 4 1 5 4 1 5 2 3 5 2 3 4 1)</p>
<p></p>
<title>2.2. queen6_6.col</title><p>&#x26;#x003c7;(G) = 7</p>
<p>Optimal color assignments:</p>
<p>(7 1 2 3 4 5 2 3 4 5 6 7 4 5 6 7 1 2 6 7 1 2 3 4 1 2 3 4 5 6 3 4 5 6 7 1) </p>
<p>(5 1 2 3 4 6 2 3 4 6 7 5 4 6 7 5 1 2 7 5 1 2 3 4 1 2 3 4 6 7 3 4 6 7 5 1)</p>
<p>(1 3 6 4 5 7 5 7 2 1 3 6 3 6 4 5 7 2 7 2 1 3 6 4 6 4 5 7 2 1 2 1 3 6 4 5)</p>
<p>(3 2 5 6 7 4 4 6 7 2 1 5 2 5 1 3 6 7 1 4 2 7 5 3 5 7 3 1 4 6 6 1 4 5 3 2)</p>
<p></p>
<p></p>
<title>2.3. queen7_7.col</title><p>&#x26;#x003c7;(G) = 7</p>
<p>Optimal color assignments:</p>
<p>(5 6 1 3 4 7 2 7 2 5 6 1 3 4 3 4 7 2 5 6 1 6 1 3 4 7 2 5 2 5 6 1 3 4 7 4 7 2 5 6 1 3 1 3 4 7 2 5 6)</p>
<p>(1 2 3 4 5 6 7 3 4 5 6 7 1 2 5 6 7 1 2 3 4 7 1 2 3 4 5 6 2 3 4 5 6 7 1 4 5 6 7 1 2 3 6 7 1 2 3 4 5)</p>
<title>2.4. queen8_8.col</title><p>&#x26;#x003c7;(G) = 9</p>
<p>Optimal color assignments:</p>
<p>(1 2 3 4 5 6 7 8 3 4 1 6 8 2 5 9 5 8 9 7 4 3 6 2 6 7 2 5 9 8 1 4 2 5 6 1 3 4 9 7 9 3 4 2 6 7 8 5 8 6 7 9 1 5 2 3 7 1 5 8 2 9 4 6)</p>
</sec><sec id="sec3">
<title>Conclusions</title><p>This article presented some of the solutions obtained for queen graphs using evolutionary methods.</p>
</sec>
  </body>
  <back>
    <ref-list>
      <title>References</title>
      
<ref id="R1">
<label>[1]</label>
<mixed-citation publication-type="other">Michael R. Garey; David S. Johnson: Computers and Intractability: A Guide to the Theory of NP-Completeness. W. H. Freeman and Company, New York (1979)
</mixed-citation>
</ref>
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<mixed-citation publication-type="other">http://cedric.cnam.fr/~porumbed/graphs/
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<mixed-citation publication-type="other">http://dimacs.rutgers.edu/programs/challenge/
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<label>[4]</label>
<mixed-citation publication-type="other">R. Marappan and G. Sethumadhavan, "A New Genetic Algorithm for Graph Coloring," 2013 Fifth International Confer-ence on Computational Intelligence, Modelling and Simulation, 2013, pp. 49-54, doi: 10.1109/CIMSim.2013.17.
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</ref>
<ref id="R5">
<label>[5]</label>
<mixed-citation publication-type="other">G. Sethumadhavan and R. Marappan, "A genetic algorithm for graph coloring using single parent conflict gene crossover and mutation with conflict gene removal procedure," 2013 IEEE International Conference on Computational Intelligence and Computing Research, 2013, pp. 1-6, doi: 10.1109/ICCIC.2013.6724190.
</mixed-citation>
</ref>
<ref id="R6">
<label>[6]</label>
<mixed-citation publication-type="other">Marappan, R., Sethumadhavan, G. Solution to Graph Coloring Using Genetic and Tabu Search Procedures. Arab J Sci Eng 43, 525-542 (2018). https://doi.org/10.1007/s13369-017-2686-9
</mixed-citation>
</ref>
<ref id="R7">
<label>[7]</label>
<mixed-citation publication-type="other">Marappan, R.; Sethumadhavan, G. Complexity Analysis and Stochastic Convergence of Some Well-known Evolutionary Operators for Solving Graph Coloring Problem. Mathematics 2020, 8, 303. https://doi.org/10.3390/math8030303
</mixed-citation>
</ref>
<ref id="R8">
<label>[8]</label>
<mixed-citation publication-type="other">Marappan, R., Sethumadhavan, G. Solving Graph Coloring Problem Using Divide and Conquer-Based Turbulent Particle Swarm Optimization. Arab J Sci Eng (2021). https://doi.org/10.1007/s13369-021-06323-x
</mixed-citation>
</ref>
    </ref-list>
  </back>
</article>