A note on the Erdos-Farber-Lovász conjecture

نویسندگان

  • Bill Jackson
  • G. Sethuraman
  • Carol A. Whitehead
چکیده

A hypergraph H is linear if no two distinct edges of H intersect in more than one vertex and loopless if no edge has size one. A q-edge-colouring of H is a colouring of the edges of H with q colours such that intersecting edges receive different colours. We use ∆H to denote the maximum degree of H. A well known conjecture of Erdös, Farber and Lovász is equivalent to the statement that every loopless linear hypergraph on n vertices can be n-edge-coloured. In this note we show that the conjecture is true when the partial hypergraph S of H determined by the edges of size at least three can be ∆S-edge-coloured and satisfies ∆S ≤ 3. In particular, the conjecture holds when S is unimodular and ∆S ≤ 3.

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عنوان ژورنال:
  • Discrete Mathematics

دوره 307  شماره 

صفحات  -

تاریخ انتشار 2007