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        <identifier>oai:drops-oai.dagstuhl.de:9019</identifier>
        <datestamp>2024-03-06T10:43:10Z</datestamp>
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          <dc:title>NP-Hardness of Coloring 2-Colorable Hypergraph with Poly-Logarithmically Many Colors</dc:title>
          <dc:creator>Bhangale, Amey</dc:creator>
          <dc:subject>Hypergraph coloring</dc:subject>
          <dc:subject>Inapproximability</dc:subject>
          <dc:subject>Schrijver graph</dc:subject>
          <dc:description>We give very short and simple proofs of the following statements: Given a 2-colorable 4-uniform hypergraph on n vertices,
1) It is NP-hard to color it with log^delta n colors for some delta&gt;0.
2) It is quasi-NP-hard to color it with O({log^{1-o(1)} n}) colors.
In terms of NP-hardness, it improves the result of Guruswam, Håstad and Sudani [SIAM Journal on Computing, 2002], combined with Moshkovitz-Raz [Journal of the ACM, 2010], by an `exponential' factor. The second result improves the result of Saket [Conference on Computational Complexity (CCC), 2014] which shows quasi-NP-hardness of coloring a 2-colorable 4-uniform hypergraph with O(log^gamma n) colors for a sufficiently small constant 1 &gt;&gt; gamma&gt;0.
Our result is the first to show the NP-hardness of coloring a c-colorable k-uniform hypergraph with poly-logarithmically many colors, for any constants c &gt;= 2 and k &gt;= 3.</dc:description>
          <dc:publisher>Schloss Dagstuhl – Leibniz-Zentrum für Informatik</dc:publisher>
          <dc:contributor>Amey Bhangale</dc:contributor>
          <dc:date>2018</dc:date>
          <dc:relation>Is Part Of LIPIcs, Volume 107, 45th International Colloquium on Automata, Languages, and Programming (ICALP 2018)</dc:relation>
          <dc:type>InProceedings</dc:type>
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          <dc:identifier>doi:10.4230/LIPIcs.ICALP.2018.15</dc:identifier>
          <dc:identifier>urn:nbn:de:0030-drops-90190</dc:identifier>
          <dc:identifier>https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ICALP.2018.15</dc:identifier>
          <dc:language>eng</dc:language>
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