{"id":{"repo_id":"usm","oai_identifier":"oai:aquila.usm.edu:masters_theses-1020"},"canonical_url":"https://search.dev.ndltd.org/etd/usm/oai:aquila.usm.edu:masters_theses-1020","repository":{"repo_id":"usm","name":"University of Southern Mississippi","base_url":"https://aquila.usm.edu/do/oai/"},"display":{"title":"Chromatic Thresholds of Regular Graphs with Small Cliques","abstract":"<p>The chromatic threshold of a class of graphs is the value <em>θ</em> such that any graph in this class with a minimum degree greater than <em>θn</em> has a bounded chromatic number. Several important results related to the chromatic threshold of triangle-free graphs have been reached in the last 13 years, culminating in a result by Brandt and Thomassé stating that any triangle-free graph on <em>n</em> vertices with minimum degree exceeding 1/3 <em>n</em> has chromatic number at most 4. In this paper, the researcher examines the class of triangle-free graphs that are additionally regular. The researcher finds that any triangle-free graph on n vertices that is regular of degree <strong>(</strong>1/4<strong>+</strong><em>a</em><strong>)</strong><em>n</em> with <em>a</em> > 0 has chromatic number bounded by <em>f <strong>(</strong>a<strong>)</strong></em>, a function of a independent of the order of the graph <em>n</em>. After obtaining this result, the researcher generalizes this method to graphs that are free of larger cliques in order to limit the possible values of the chromatic threshold for regular <em>Kr</em>-free graphs.</p>","abstract_html":"&lt;p&gt;The chromatic threshold of a class of graphs is the value &lt;em&gt;θ&lt;/em&gt; such that any graph in this class with a minimum degree greater than &lt;em&gt;θn&lt;/em&gt; has a bounded chromatic number. Several important results related to the chromatic threshold of triangle-free graphs have been reached in the last 13 years, culminating in a result by Brandt and Thomassé stating that any triangle-free graph on &lt;em&gt;n&lt;/em&gt; vertices with minimum degree exceeding 1/3 &lt;em&gt;n&lt;/em&gt; has chromatic number at most 4. In this paper, the researcher examines the class of triangle-free graphs that are additionally regular. The researcher finds that any triangle-free graph on n vertices that is regular of degree &lt;strong&gt;(&lt;/strong&gt;1/4&lt;strong&gt;+&lt;/strong&gt;&lt;em&gt;a&lt;/em&gt;&lt;strong&gt;)&lt;/strong&gt;&lt;em&gt;n&lt;/em&gt; with &lt;em&gt;a&lt;/em&gt; &gt; 0 has chromatic number bounded by &lt;em&gt;f &lt;strong&gt;(&lt;/strong&gt;a&lt;strong&gt;)&lt;/strong&gt;&lt;/em&gt;, a function of a independent of the order of the graph &lt;em&gt;n&lt;/em&gt;. After obtaining this result, the researcher generalizes this method to graphs that are free of larger cliques in order to limit the possible values of the chromatic threshold for regular &lt;em&gt;Kr&lt;/em&gt;-free graphs.&lt;/p&gt;","abstract_has_math":false,"creators":["O'Rourke, Jonathan Lyons"],"institution":null,"degree_name":"Master of Science (MS)","degree_level":"Masters Thesis","degree_discipline":"Mathematics","degree_department":null,"school":null,"contributors":["Jeremy Lyle","John Perry","Karen Kohl"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-05-01T07:00:00Z","date_published":"2014-05-01T07:00:00Z","updated_at":"2026-07-24T05:44:27Z","subjects":["chromatic number","chromatic threshold","graph theory","regular graphs"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://aquila.usm.edu/masters_theses/27","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Jeremy Lyle","John Perry","Karen Kohl"]},{"key":"dc:creator","label":"Author","values":["O'Rourke, Jonathan Lyons"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2014-06-09T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Mathematics"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Masters Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science (MS)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["chromatic number","chromatic threshold","graph theory","regular graphs"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://aquila.usm.edu/masters_theses/27"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["<p>The chromatic threshold of a class of graphs is the value <em>θ</em> such that any graph in this class with a minimum degree greater than <em>θn</em> has a bounded chromatic number. Several important results related to the chromatic threshold of triangle-free graphs have been reached in the last 13 years, culminating in a result by Brandt and Thomassé stating that any triangle-free graph on <em>n</em> vertices with minimum degree exceeding 1/3 <em>n</em> has chromatic number at most 4. In this paper, the researcher examines the class of triangle-free graphs that are additionally regular. The researcher finds that any triangle-free graph on n vertices that is regular of degree <strong>(</strong>1/4<strong>+</strong><em>a</em><strong>)</strong><em>n</em> with <em>a</em> > 0 has chromatic number bounded by <em>f <strong>(</strong>a<strong>)</strong></em>, a function of a independent of the order of the graph <em>n</em>. After obtaining this result, the researcher generalizes this method to graphs that are free of larger cliques in order to limit the possible values of the chromatic threshold for regular <em>Kr</em>-free graphs.</p>"]},{"key":"dc:title","label":"Title","values":["Chromatic Thresholds of Regular Graphs with Small Cliques"]}]}],"canonical_facts":{"dc:contributor":["Jeremy Lyle","John Perry","Karen Kohl"],"dc:creator":["O'Rourke, Jonathan Lyons"],"dc:date.available":["2014-06-09T07:00:00Z"],"dc:description.abstract":["<p>The chromatic threshold of a class of graphs is the value <em>θ</em> such that any graph in this class with a minimum degree greater than <em>θn</em> has a bounded chromatic number. Several important results related to the chromatic threshold of triangle-free graphs have been reached in the last 13 years, culminating in a result by Brandt and Thomassé stating that any triangle-free graph on <em>n</em> vertices with minimum degree exceeding 1/3 <em>n</em> has chromatic number at most 4. In this paper, the researcher examines the class of triangle-free graphs that are additionally regular. The researcher finds that any triangle-free graph on n vertices that is regular of degree <strong>(</strong>1/4<strong>+</strong><em>a</em><strong>)</strong><em>n</em> with <em>a</em> > 0 has chromatic number bounded by <em>f <strong>(</strong>a<strong>)</strong></em>, a function of a independent of the order of the graph <em>n</em>. After obtaining this result, the researcher generalizes this method to graphs that are free of larger cliques in order to limit the possible values of the chromatic threshold for regular <em>Kr</em>-free graphs.</p>"],"dc:identifier":["https://aquila.usm.edu/masters_theses/27"],"dc:subject":["chromatic number","chromatic threshold","graph theory","regular graphs"],"dc:title":["Chromatic Thresholds of Regular Graphs with Small Cliques"],"thesis:degree_discipline":["Mathematics"],"thesis:degree_level":["Masters Thesis"],"thesis:degree_name":["Master of Science (MS)"]},"updated_at":"2026-07-24T05:44:27Z"}