Extremal interval graphs
Jürgen Eckhoff · Journal of Graph Theory · 1993
Abstract An interval graph is said to be extremal if it achieves, among all interval graphs having the same number of vertices and the same clique number, the maximum possible number of edges. We give an intrinsic characterization of extremal interval graphs and derive recurrence relations for the numbers of such graphs. © 1993 John Wiley & Sons, Inc.