Edge-distance-regular graphs are distance-regular

نویسندگان

  • M. Cámara
  • Cristina Dalfó
  • Charles Delorme
  • Miguel Angel Fiol
  • H. Suzuki
چکیده

A graph is edge-distance-regular when it is distance-regular around each of its edges and it has the same intersection numbers for any edge taken as a root. In this paper we give some (combinatorial and algebraic) proofs of the fact that every edge-distance-regular graph Γ is distance-regular and homogeneous. More precisely, Γ is edge-distance-regular if and only if it is bipartite distance-regular or a generalized odd graph. Also, we obtain the relationships between some of their corresponding parameters, mainly, the distance polynomials and the intersection numbers.

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عنوان ژورنال:
  • J. Comb. Theory, Ser. A

دوره 120  شماره 

صفحات  -

تاریخ انتشار 2013