Abstract
Manca has derived an efficient matrix method for testing a given graph to see whether or not it is a threshold graph.
Chvátal and Hammer introduced these graphs which can be defined by the condition that they do not contain as induced subgraphs 2K2, P4, or C4. Implicit in the results of Manca is a structural description of such graphs. Our object is to display the structure of threshold graphs explicitly by a combination of contraction and homomorphism and the use of the bipartite-adjacency matrix.
Riassunto
L’autore riprende un metodo proposto da P. Manca per stabilire se un dato grafo è un « threshold graph » (secondo la terminologia di Chvátal e Hammer), e si propone di porre in evidenza la struttura di questa varietà di grafi facendo ricorso ad una combinazione di contrazioni e omomorfismi e all’uso di una « bipartite-adjacency-matrix ».
Similar content being viewed by others
References
R. Brualdi, F. Harary, Z. Miller,Bigraphs versus digraphs via matrices. J. Graph Theory, to appear.
V. Chvátal, P. L. Hammer,Aggregation inequalities in integer programming, Annals Discrete Math. 1 (1977) 145–162.
F. Harary,Graph theory, Addison-Wesley, Reading (1969).
P. Manca,On a simple characterization of threshold graphs, Rivista di Matematica per le Scienze Economiche e Sociali, 2 (1979) 3–8.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Harary, F. The structure of threshold graphs. Rivista di Matematica per le Scienze Economiche e Sociali 2, 169–172 (1979). https://doi.org/10.1007/BF02620304
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02620304