Fractional Colouring and Hadwiger's Conjecture
نویسندگان
چکیده
This is easy for p 3, true but difficult for p=4 and 5 (in both cases [9, 6] it is equivalent to the four-colour theorem [1, 2, 7]), and open for p 6. It is therefore of interest to examine weakenings of (1.1). If G has no Kp+1 minor, the best upper bound known on its chromatic number is O( p(log p) ). This follows easily from the following theorem of Kostochka [5] or Thomason [8]. Article No. TB981835
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عنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 74 شماره
صفحات -
تاریخ انتشار 1998