An Improvement of Hind's Upper Bound on the Total Chromatic Number

نویسندگان

  • Amanda G. Chetwynd
  • Roland Häggkvist
چکیده

The purpose of this note is to improve Hind's theorem for graphs with large chromatic number by essentially reducing the power of / from | to | + e (the exact statement of our result is given in equations (4)-(6) below). Our proof uses a lemma which in words states that, if we assign to each vertex x in a fc-chromatic r-edge-chromatic multigraph a colour/(x) from {1,2,. . . ,r}, then there exists a proper (r + fc)-edge-colouring which on each edge xy assigns a colour from {1,2,... , r + k} — f(x) — f(y). Using terminology from our earlier work [2], we can formulate this as

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عنوان ژورنال:
  • Combinatorics, Probability & Computing

دوره 5  شماره 

صفحات  -

تاریخ انتشار 1996