On the hamiltonian index and the radius of a graph Original Research Article

Catlin et al. [1, Corollary 9A] characterised the graphs G with the property that ham(G) > rad(G) + 1 where ham(G) and rad(G) stand for the hamiltonian index and the radius of G, respectively. Here a slightly stronger result is presented. In effect, the graphs for which ham(G) > rad(G) holds are characterised in a similar way.