We make further progress towards the forbidden-induced-subgraph characterization of the graphs with Hall number \(\leq 2\). We solve several problems posed in [4] and, in the process, describe all “partial wheel” graphs with Hall number \(\geq 2\) with every proper induced subgraph having Hall number \(\leq 2\).
Citation
P.D. Johnson Jr., E.B. Wantland. Which Graphs Have Hall Number Two?[J], Ars Combinatoria, Volume 065. 39-64. .