Аноним

K-Cyclic chromatic number: различия между версиями

Материал из WikiGrapp
нет описания правки
Нет описания правки
Нет описания правки
 
Строка 3: Строка 3:
The '''<math>\,k</math>-cyclic chromatic number''' <math>\,\chi_{k}(G)</math> of a [[plane graph]] is the smallest number of colours in a [[vertex]] [[Coloring, colouring|colouring]] of <math>\,G</math> such that no face of size at most <math>\,k</math> has two boundary vertices of the same colour. It is easy to see that the Four Colour Theorem may be stated in the form:
The '''<math>\,k</math>-cyclic chromatic number''' <math>\,\chi_{k}(G)</math> of a [[plane graph]] is the smallest number of colours in a [[vertex]] [[Coloring, colouring|colouring]] of <math>\,G</math> such that no face of size at most <math>\,k</math> has two boundary vertices of the same colour. It is easy to see that the Four Colour Theorem may be stated in the form:


        <math>\,\chi_{3}(G) \leq 4</math>
<math>\,\chi_{3}(G) \leq 4</math>


for every plane graph <math>\,G</math>.
for every plane graph <math>\,G</math>.