Some mader-perfect graph classes
نویسندگان
چکیده
The dichromatic number of D, denoted by χ→(D), is the smallest integer k such that D admits an acyclic k-coloring. We use maderχ→(F) to denote if χ→(D)≥k, then contains a subdivision F. A digraph F called Mader-perfect for every subdigraph F′ F, maderχ→(F′)=|V(F′)|. extend octi digraphs larger class and prove it Mader-perfect, which generalizes result Gishboliner, Steiner Szabó [Dichromatic forced subdivisions, J. Comb. Theory, Ser. B 153 (2022) 1–30]. also show K proper C↔4 except obtained from deleting arbitrary arc, Mader-perfect.
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ژورنال
عنوان ژورنال: Applied Mathematics and Computation
سال: 2023
ISSN: ['1873-5649', '0096-3003']
DOI: https://doi.org/10.1016/j.amc.2023.127968