Digraphs of degree 3 and order close to the moore bound

نویسندگان

  • Edy Tri Baskoro
  • Mirka Miller
  • Ján Plesník
  • Stefan Znám
چکیده

It is known that Moore digraphs of degree d > 1 and diameter k > 1 do not exist (see 20] or 5]). Furthermore, for degree 2, it is shown that for k 3 there are no digraphs of order`close' to, i.e., one less than, Moore bound 18]. In this paper, we shall consider digraphs of diameter k, degree 3 and number of vertices one less than Moore bound. We give a necessary condition for the existence of such digraphs and, using this condition, we deduce that such digraphs do not exist for innnitely many values of the diameter.

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عنوان ژورنال:
  • Journal of Graph Theory

دوره 20  شماره 

صفحات  -

تاریخ انتشار 1995