Odd holes in bull-free graphs

@article{Chudnovsky2018OddHI,
  title={Odd holes in bull-free graphs},
  author={M. Chudnovsky and Vaidy Sivaraman},
  journal={ArXiv},
  year={2018},
  volume={abs/1704.04262}
}
The complexity of testing whether a graph contains an induced odd cycle of length at least five is currently unknown. In this paper we show that this can be done in polynomial time if the input graph has no induced subgraph isomorphic to the bull (a triangle with two disjoint pendant edges). 
Perfect divisibility and 2‐divisibility
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FINDING LARGE H-COLORABLE SUBGRAPHS
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Test if G contains C 5 by enumerating all 5-tuples. If yes, stop and output: " G contains an odd hole
  • Test if G contains C 5 by enumerating all 5-tuples. If yes, stop and output: " G contains an odd hole