Proper Colorings of Plane Quadrangulations Without Rainbow Faces
نویسندگان
چکیده
We consider a proper coloring of plane graph such that no face is rainbow, where rainbow if any two vertices on its boundary have distinct colors. Such said to be anti-rainbow. A quadrangulation G in which all faces are bounded by cycle length 4. In this paper, we show the number colors anti-rainbow does not exceed $$3\alpha (G)/2$$ , $$\alpha (G)$$ independence G. Moreover, minimum degree 3 or 3-connected, then bound can improved $$5\alpha (G)/4$$ $$7\alpha (G)/6 + 1/3$$ respectively. All these bounds tight.
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ژورنال
عنوان ژورنال: Graphs and Combinatorics
سال: 2021
ISSN: ['1435-5914', '0911-0119']
DOI: https://doi.org/10.1007/s00373-021-02350-5