On coindices of graphs and their complements

Abstract

© 2017 Elsevier Inc. It was recently discovered (Gutman et al., 2015) that the coindex of the first Zagreb index of any graph is equal to the coindex of the complement of this graph. We examine the possibility that an analogous equality holds for other topological indices. It is shown that there are several classes of graphs and classes of topological indices for which such a relation is obeyed.