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The extended binary quadratic residue code of length 42 holds a 3-design

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 نشر من قبل Patrick Sol\\'e
 تاريخ النشر 2021
  مجال البحث الهندسة المعلوماتية
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The codewords of weight $10$ of the $[42,21,10]$ extended binary quadratic residue code are shown to hold a design of parameters $3-(42,10,18).$ Its automorphism group is isomorphic to $PSL(2,41)$. Its existence can be explained neither by a transitivity argument, nor by the Assmus-Mattson theorem.



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