• Sepehr Hajebi, Holes, hubs and bounded treewidth

    Zoom ID: 869 4632 6610 (ibsdimag)

    A hole in a graph $G$ is an induced cycle of length at least four, and for every hole $H$ in $G$, a vertex $h\in G\setminus H$ is called a $t$-hub for $H$ if $h$ has at least $t$ neighbor in $H$. Sintiari and Trotignon were the first to construct graphs with arbitrarily large treewidth

  • Sepehr Hajebi, The pathwidth theorem for induced subgraphs

    Room B332 IBS (기초과학연구원)

    We present a full characterization of the unavoidable induced subgraphs of graphs with large pathwidth. This consists of two results. The first result says that for every forest H, every graph of sufficiently large pathwidth contains either a large complete subgraph, a large complete bipartite induced minor, or an induced minor isomorphic to H. The