Generalized line graphs

Abstract

Generalized line graphs extend the ideas of both line graphs and cocktail party graphs. They were originally motivated by spectral considerations. in this paper several (nonspectral) classical theorems about line graphs are extended to generalized line graphs, including the derivation and construction of the 31 minimal nongeneralized line graphs, a Krausz‐type covering characterization, and Whitney‐type theorems on isomorphisms and automorphisms.