Abstract
The spread s(G) of a graph G is defined as s(G) = maxi,j|λ i − λ j |, where the maximum is taken over all pairs of eigenvalues of G. Let U(n,k) denote the set of all unicyclic graphs on n vertices with a maximum matching of cardinality k, and U *(n,k) the set of triangle-free graphs in U(n,k). In this paper, we determine the graphs with the largest and second largest spectral radius in U *(n,k), and the graph with the largest spread in U(n,k).
Similar content being viewed by others
References
Chang A., Tian F. (2003) On the spectral radius of unicyclic graphs with perfect matchings. Linear Algebra Appl. 370: 237–250
Cvetkoić D., Doob M., Sachs H. (1980) Spectra of Graphs–Theory and Applications. Academic Press, New York
Cvetkoić D., Petrić M. (1984) A table of connected graphs on six vertices. Discrete Math. 50: 37–49
Cvetkoić D., Rowlinson P. (1987) Spectra of unicyclic graphs. Graph Combin. 3: 7–23
Cvetkoić D., Rowlinson P., Simić S. (1997). Eigenspaces of Graphs. Cambridge Univ, Cambridge
Gergory D., Hershkowitz D., Kirkland S. (2001) The spread of the spectrum of a graph, Linear Algebra Appl. 332–334: 23–35
Guo J., Tan S. (2001) On the spectral radius of trees.Linear Algebra Appl. 329: 1–8
Hou Y., Li J. (2002) Bounds on the largest eigenvalues of trees with a given size of matching. Linear Algebra Appl. 342: 203–217
Johnson C., Kumar R., Wolkowicz H. (1985) Lower bounds for the spread of a matrix. Linear Algebra Appl. 71: 161–173
Li Q., Feng K. (1979) On the largest eigenvalue of graphs, Acta Math. Appl. Sinica 2: 167–175
Mirsky L. (1956) The spread of a matrix. Mathematika 3: 127–130
Petrović M. (1983) On graphs whose spectral spread does not exceed 4. Publ. Inst. Math. (Beograd) 34 (48): 169–174
Simić S. (1987) On the largest eigenvalue of unicyclic graphs, Publ. Inst. Math. (Beograd) 42(56): 13–19
Yu A., Tian F. (2004) On the spectral radius of unicyclic graphs. MATCH commun. Math. Comput. Chem. 51:97–109
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Li, X., Zhang, J. & Zhou, B. The spread of unicyclic graphs with given size of maximum matchings. J Math Chem 42, 775–788 (2007). https://doi.org/10.1007/s10910-006-9141-6
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10910-006-9141-6