Pushable chromatic number of graphs with degree constraints
نویسندگان
چکیده
Pushable homomorphisms and the pushable chromatic number χp of oriented graphs were introduced by Klostermeyer MacGillivray in 2004. They notably observed that, for any graph G⃗, we have χp(G⃗)≤χo(G⃗)≤2χp(G⃗), where χo(G⃗) denotes G⃗. This stands as first general bounds on χp. parameter was further studied later works. work is dedicated to fulfilling particular degree conditions. For all Δ≥29, prove that maximum value a connected with Δ lies between 2Δ2−1 (Δ−3)⋅(Δ−1)⋅2Δ−1+2 which implies an improved bound same family graphs. subcubic graphs, is, when Δ≤3, then 6 or 7. We also average less than 3 5 6. The former upper 7 holds planar girth at least
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2021
ISSN: ['1872-681X', '0012-365X']
DOI: https://doi.org/10.1016/j.disc.2020.112151