A Modified Bordered Construction for Self-dual Codes From Group Rings

  • Joe Gildea
  • Abidin Kaya
  • Alexander Tylyshchak
  • Bahattin Yildiz
Keywords: Group rings, Self-dual codes, Codes over rings, Bordered constructions


We describe a bordered construction for self-dual codes coming from group rings. We apply the constructions coming from the cyclic and dihedral groups over several alphabets to obtain extremal binary self-dual codes of various lengths. In particular we find a new extremal binary self-dual code of length 78.


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