Sumsets in dihedral groups

نویسندگان

  • Shalom Eliahou
  • Michel Kervaire
چکیده

Let Dn be the dihedral group of order 2n. For all integers r, s such that 1 ≤ r, s ≤ 2n, we give an explicit upper bound for the minimal size μDn (r, s) = min |A · B| of sumsets (product sets) A · B, where A and B range over all subsets of Dn of cardinality r and s respectively. It is shown by construction that μDn (r, s) is bounded above by the known value of μG (r, s), where G is any abelian group of order 2n. We conjecture that this upper bound is sharp, and prove that it really is if n is a prime power. © 2005 Elsevier Ltd. All rights reserved.

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عنوان ژورنال:
  • Eur. J. Comb.

دوره 27  شماره 

صفحات  -

تاریخ انتشار 2006