A logarithmic approximation of linearly-ordered colourings
2024 (Engelska)Ingår i: Approximation, Randomization, and Combinatorial Optimization. Algorithms and Techniques, APPROX/RANDOM 2024, Schloss Dagstuhl- Leibniz-Zentrum fur Informatik GmbH, Dagstuhl Publishing , 2024, artikel-id 7Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]
A linearly ordered (LO) k-colouring of a hypergraph assigns to each vertex a colour from the set {0, 1, . . ., k − 1} in such a way that each hyperedge has a unique maximum element. Barto, Batistelli, and Berg conjectured that it is NP-hard to find an LO k-colouring of an LO 2-colourable 3-uniform hypergraph for any constant k ≥ 2 [STACS’21] but even the case k = 3 is still open. Nakajima and Živný gave polynomial-time algorithms for finding, given an LO 2-colourable 3-uniform hypergraph, an LO colouring with O*(√n) colours [ICALP’22] and an LO colouring with O*(√3 n) colours [ACM ToCT’23]. Very recently, Louis, Newman, and Ray gave an SDP-based algorithm with O*(√5 n) colours. We present two simple polynomial-time algorithms that find an LO colouring with O(log2(n)) colours, which is an exponential improvement.
Ort, förlag, år, upplaga, sidor
Schloss Dagstuhl- Leibniz-Zentrum fur Informatik GmbH, Dagstuhl Publishing , 2024. artikel-id 7
Nyckelord [en]
Approximation, Hypergraph, Linear ordered colouring, Promise Constraint Satisfaction Problems
Nationell ämneskategori
Datavetenskap (datalogi) Diskret matematik
Identifikatorer
URN: urn:nbn:se:kth:diva-354305DOI: 10.4230/LIPIcs.APPROX/RANDOM.2024.7ISI: 001545634500007Scopus ID: 2-s2.0-85204434826OAI: oai:DiVA.org:kth-354305DiVA, id: diva2:1902964
Konferens
27th International Conference on Approximation Algorithms for Combinatorial Optimization Problems, APPROX 2024 and the 28th International Conference on Randomization and Computation, RANDOM 2024, August 28-30, 2024, London, United Kingdom of Great Britain and Northern Ireland
Anmärkning
Part of ISBN: 9783959773485
QC 20241003
2024-10-022024-10-022025-12-08Bibliografiskt granskad