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Title: Complexity of Ck-Coloring in Hereditary Classes of Graphs
For a graph F, a graph G is F-free if it does not contain an induced subgraph isomorphic to F. For two graphs G and H, an H-coloring of G is a mapping f : V (G) → V (H) such that for every edge uv ∈ E(G) it holds that f(u)f(v) ∈ E(H). We are interested in the complexity of the problem H-Coloring, which asks for the existence of an H-coloring of an input graph G. In particular, we consider H-Coloring of F-free graphs, where F is a fixed graph and H is an odd cycle of length at least 5. This problem is closely related to the well known open problem of determining the complexity of 3-Coloring of Pt-free graphs. We show that for every odd k ≥ 5 the Ck-Coloring problem, even in the precoloring-extension variant, can be solved in polynomial time in P9-free graphs. On the other hand, we prove that the extension version of Ck-Coloring is NP-complete for F-free graphs whenever some component of F is not a subgraph of a subdivided claw.  more » « less
Award ID(s):
1763817
PAR ID:
10164201
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
European Symposium on Algorithms
Page Range / eLocation ID:
31:1 - 31:15
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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