An extremal [72, 36, 16] binary code has no automorphism group containing Z2 x Z4, Q8, or Z10

نویسنده

  • Gabriele Nebe
چکیده

Abstract. Let C be an extremal self-dual binary code of length 72 and g ∈ Aut(C) be an automorphism of order 2. We show that C is a free F2〈g〉 module and use this to exclude certain subgroups of order 8 of Aut(C). We also show that Aut(C) does not contain an element of order 10. Combining these results with the ones obtained in earlier papers we find that the order of Aut(C) is either 5 or divides 24. If 8 divides the order of Aut(C) then its Sylow 2-subgroup is either D8 or Z2 × Z2 × Z2.

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منابع مشابه

The Automorphism Group of an Extremal {72, 36, 16} Code Does Not Contain Z7, Z3×Z3, or D10

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عنوان ژورنال:
  • Finite Fields and Their Applications

دوره 18  شماره 

صفحات  -

تاریخ انتشار 2012