A positive instance of Scott's Conjecture on induced subdivisions
Abstract
For a graph , denotes the chromatic number of and denotes the size of the largest clique in . A hereditary class of graphs is called -bounded if there is a function such that for each graph in the class, . Scott (1997) conjectured that for every graph , the class of graphs which do not contain any subdivision of as an induced subgraph is -bounded. He proved his conjecture when is a tree and when is the complete graph on four vertices, . Esperet and Trotignon (2019) proved that the conjecture holds when is with one edge subdivided once. Scott's conjecture was disproved by Pawlik et al. (2014). Chalopin et al. (2016) gave more counterexamples including the graph obtained from by subdividing each edge of a 4-cycle once. We prove that the conjecture holds when consists of a complete bipartite graph with and additional vertex which has exactly two neighbours, on the same side of the bipartition. As a special case, this proves Scott's conjecture when is obtained from by subdividing two disjoint edges.
Keywords
Cite
@article{arxiv.2602.11990,
title = {A positive instance of Scott's Conjecture on induced subdivisions},
author = {Kathie Cameron and Ni Luh Dewi Sintiari and Sophie Spirkl},
journal= {arXiv preprint arXiv:2602.11990},
year = {2026}
}