We study perfect error correcting codes in which the codewords are protected by Hamming spheres of distinct protective radii. These codes have been introduced by Cohen, Montaron and Frankl [3, 4, 10].

We are interested in a special class of these codes, namely the strongly tactical ones, introduced in [6]. There are relations with uniformly packed codes [11]. We give conditions on the existence of strongly tactical codes, in particular a generalization of Lloyd's Theorem, and use these conditions to prove some characterization theorems. In particular, we shall characterize the punctured Golay codes and an infinite class of strongly tactical codes.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1986

Authors and Affiliations

  • Michael Gundlach
    • 1
  1. 1.Fachbereich MathematikJohannes Gutenberg-UniversitätMainzFRG

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