H-colouring Pt-free graphs in subexponential time
نویسندگان
چکیده
منابع مشابه
$H$-colouring $P_t$-free graphs in subexponential time
A graph is called Pt-free if it does not contain the path on t vertices as an induced subgraph. Let H be a multigraph with the property that any two distinct vertices share at most one common neighbour. In this note, we show that for any α > 1 − ⌊t/2⌋−1 the generating function for (list) graph homomorphisms from G to H can be calculated in subexponential time O ( 2|V (G)| α) in the class of Pt-...
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It is an old open question in algorithmic graph theory to determine the complexity of the Maximum Independent Set problem on Pt-free graphs, that is, on graphs not containing any induced path on t vertices. So far, polynomial-time algorithms are known only for t ≤ 5 [Lokshtanov et al., SODA 2014, pp. 570–581, 2014]. Here we study the existence of subexponentialtime algorithms for the problem: b...
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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 2019
ISSN: 0166-218X
DOI: 10.1016/j.dam.2019.04.010